Akershus Fortress: A Royal Castle and Military Stronghold in Norway
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On this page29 sections
History
Akershus Fortress is a medieval castle and later military stronghold in Oslo, Norway, built by the Norwegian monarchy during the late thirteenth or early fourteenth century to defend the city and provide a royal residence. It stands on the Akersneset peninsula beside the Oslofjord, and its name derives from the Aker farm that formerly owned the site. The fortress later gave its name to the Akershus fief, county, and administrative district.
Foundation and royal residence
The precise date of construction is uncertain. An earlier defensive installation may have stood on the peninsula before 1287, but the castle is generally dated to the 1290s or to around 1300, during the reign of Håkon V Magnusson, king of Norway from 1299 to 1319. Akershus was first mentioned in writing in 1300, when a royal document associated with Oslo’s Mariakirken was stored there. One historical tradition regards Jakob Nielsen as the builder of the first castle.
The fortress arose after Alv Erlingsson attacked Oslo in 1287, an event that exposed the weakness of the city’s existing defenses. The rocky promontory offered a strong position. Steep ground protected the site toward the fjord, marshes lay toward Ekeberg, and access from the north was limited by a narrow ridge. During Håkon V’s reign, Akershus became a royal residence and eventually replaced Bergenhus as the principal royal seat. Håkon later moved the seat of government to Oslo, and the fortress may already have contained a royal chancery at that time.
Akershus resisted a Swedish-led siege in 1308 by Duke Erik of Södermanland and his Norwegian supporters. A local Norwegian peasant army helped break the siege in a battle near Oslo. In the 1330s, Norwegian magnates opposed to the royal union with Sweden temporarily controlled the fortress. Håkon VI, Håkon V’s grandson and king of Norway from 1343 to 1380, lived there frequently during the 1360s and 1370s and ordered extensive building works.
Olav, the son of Håkon VI and Margaret I, was probably born at Akershus. He became king of Denmark and Norway, ruling from 1380 until his death in 1387. Margaret later established the Kalmar Union, the late-medieval political union that placed Denmark, Norway, and Sweden under a shared monarchy.
Sieges, political conflict, and reconstruction
The fortress was unsuccessfully besieged in 1449 and 1450 during the succession struggle between Christian I and Karl VIII. In 1502, Knut Alvsson captured Akershus from the Danish commander Peder Griis. Alvsson was later killed during negotiations with Henrik Krummedike, and royal forces recovered the fortress. Tradition holds that Alvsson’s body was left unburied for twelve years in one of the towers as a warning to opponents.
Swedish forces besieged Akershus in 1523. Hans Mule, the commander, ordered Oslo’s inhabitants to burn much of the city so that the attackers could not use its buildings for shelter or obtain supplies there. The Swedish forces withdrew. A more destructive event followed in 1527, when lightning caused a major fire that severely damaged the castle, including the northern and western wings, Knutstårnet, Fadeburet, and Vågehalstårnet. The upper part of Vågehalstårnet was later removed. The damaged medieval castle was rebuilt and transformed into a Renaissance palace.
Christian II besieged Akershus from 1531 to 1532 while attempting to regain his throne. Only about twenty to thirty defenders were present when the siege began, but Christian’s attacks failed. Forces from Denmark and Lübeck relieved the fortress in 1532, after which it was repaired and strengthened. During the siege, the commander Mogens Gyldenstjerne attacked, plundered, and burned Hovedøya Monastery. Stone from the monastery was later reused in repairs and fortifications at Akershus, and the monastery’s tenant farmers came under the authority of the lord of Akershus.
Swedish forces returned during the Northern Seven Years’ War, a conflict between Sweden and Denmark-Norway that lasted from 1563 to 1570. They besieged Akershus in 1567, and Christen Munk again ordered Oslo burned so that the attackers would lack shelter and supplies. The fortress survived, although the surrounding city was largely destroyed.
Renaissance palace and artillery fortress
From 1593, Christian IV, king of Denmark and Norway from 1588 to 1648, initiated a large modernization to meet the growing effectiveness of artillery. The works followed the Italian bastion system, an early-modern method using angular bastions, earth-filled ramparts, connecting walls, ditches, and covered ways to resist cannon fire and provide overlapping defensive fire. The fortification was financed partly by special taxes and partly by compulsory labor, including the transport of bricks by women.
The principal phases of the Renaissance defenses took place from 1593 to 1604 and from 1616 to 1646. Dutch engineers and builders, including Hans van Steenwinkel and Jan Jansen, continued the design and construction. At the same time, the medieval castle was remodeled as a Renaissance palace. Royal and gubernatorial apartments, representative rooms, towers, and the castle church were altered or renewed.
After the Oslo fire of 1624, Christian IV ordered the city to be moved beside the fortress. The new city, Christiania, was laid out to the north as a planned fortified town, with Akershus serving as its citadel. The relocation had a military purpose: the new settlement would be easier to defend and less useful to an enemy. Akershus continued to function as a royal residence and hosted royal homages and assemblies of the estates. After absolutism was introduced in 1660, its representative role declined and the complex became increasingly focused on military use. The Overhoffretten, then Norway’s highest court, remained its principal civilian institution during the eighteenth century.
Further defensive works followed the wars and territorial losses of the seventeenth century. Isaac van Geelkerck and Willem Coucheron directed major projects, including the completion of the inner fortress, the Hornverk, new bastions, ramparts, ditches, and the lower defensive area known as Hovedtangen or Nedrevolls festning.
During King Karl XII’s Norwegian campaign in 1716, the enlarged fortress was attacked by a Swedish army of about 10,000 men. Colonel Jørgen Christopher von Klenow organized more than 3,000 defenders inside Akershus. The fortress suffered little damage, and the Swedish campaign failed. The siege was abandoned after Danish reinforcements cut the Swedish supply line.
Decline, prison, and nineteenth-century restoration
By about 1750, the fortifications were considered militarily outdated and Akershus had lost much of its earlier strategic importance. After the union between Norway and Sweden in 1814, the lower defensive area was ordered to be demolished, and the fortress was initially deactivated in 1815. During the nineteenth century, the complex deteriorated. Parts of the outer area were released for public and private construction, while the remaining buildings served for storage, military purposes, and the National Archive. The fortification grounds also became a recreational area for Oslo residents.
Akershus contained a prison and penal-labor institution commonly called the Slaveriet. Prisoners could be assigned to public works or leased to private employers. Notable prisoners included Gjest Baardsen and Ole Høiland, and in the nineteenth century the fortress was regarded as Norway’s strictest prison.
After the 1852 Laestadian Sami uprising in Kautokeino, most of the male participants, except the executed leaders Aslak Hætta and Mons Somby, were imprisoned at Akershus. The women were imprisoned in Trondheim, and several prisoners died in captivity. Lars Hætta, imprisoned at the age of eighteen, was given the opportunity to produce the first translation of the Bible into Northern Sami.
Between 1858 and 1870, Wilhelm von Hanno and Heinrich Ernst Schirmer directed a program that restored and expanded the fortress. It added or reconstructed an artillery magazine, prison buildings, a prison church, riding facilities, a commander’s house, storage buildings, and other military structures.
Preservation and twentieth-century history
By the end of the nineteenth century, deterioration and pressure for building land led to increasingly frequent proposals for demolition. Christian Krohg recorded the fortress’s poor condition, while Peter Andreas Blix, Gustav Storm, and Harry Fett argued for its preservation. The Norwegian parliament approved a restoration program in 1896 and 1897.
Restoration continued from the early twentieth century until about 1960. Holger Sinding-Larsen worked actively from 1905 to 1925, Arnstein Arneberg joined the project from 1929, and Gerhard Fischer also participated. The work repaired walls, cellars, floors, ceilings, roofs, and facades. It combined medieval and later fabric rather than attempting to recreate one supposedly pure historical phase, although the Renaissance period became the principal interpretive theme. The program was interrupted by the war years from 1940 to 1945 and was largely completed in 1960 or 1962. Stephan Tschudi-Madsen assumed professional responsibility for the complex from 1960. A further major restoration in 2010 identified damage caused by cement and by the removal of earlier white lime coatings, as well as surviving evidence of earlier ocher-colored lime finishing.
During the German occupation of Norway, from 1940 to 1945, Akershus served as a prison for political detainees and a place of execution. Forty-two Norwegians were executed there in February and March 1945, including victims of reprisals after the killing of police chief Karl Marthinsen.
Vidkun Quisling was proclaimed minister-president at Akershus on 1 February 1942 by the German occupation authorities. After the war, he was imprisoned and executed at the fortress by firing squad on 24 October 1945. Albert Viljam Hagelin and Ragnar Skancke were also executed there, as was Siegfried Fehmer, the German Gestapo chief of Oslo, on 16 March 1948. Norwegian forces took over Akershus on 11 May 1945, when the German garrison handed it to Terje Rollem on behalf of the Norwegian resistance movement.
Royal, military, and commemorative functions
After the war, Akershus became an important venue for state representation. It hosted celebrations for King Haakon VII’s seventy-fifth birthday in 1947, and the transfer ceremony for the 1978 Nobel Peace Prize awarded to Menachem Begin was held there after protests made the original venue unsuitable.
The Royal Mausoleum was established in 1948 in the crypt of the castle church. It contains the interments of King Haakon VII, Queen Maud, King Olav V, and Crown Princess Märtha. The crypt also encloses the remains of King Sigurd I and the skulls of King Håkon V and Queen Eufemia.
Akershus remains a military complex under a commandant. It contains military offices, schools, stores, workshops, the integrated leadership of the Norwegian Armed Forces, the Norwegian Defence Museum, and the Norwegian Resistance Museum. The palace rooms continue to serve official state-representation functions, while the outer grounds also function as a recreational and green area. The Resistance Museum occupies the former Det dobbelte batteri and an associated timber-framed building, interpreting the occupation of Norway during the Second World War with particular emphasis on the resistance movement.
The medieval castle and Renaissance palace are protected under Norway’s cultural-heritage legislation. The entire fortress, including its outer works, was protected by the Norwegian Directorate for Cultural Heritage on 17 December 2014. The complex is administered by Forsvarsbygg, the property and facilities organization of the Norwegian armed forces.
Remains
Akershus covers approximately 170 daa and contains about 91,000 square metres of building area. The complex is divided into the castle, the inner bastion fortress, and the outer fortress area. The inner area preserves the main medieval and early-modern defenses, while the outer area contains many nineteenth-century military buildings and former defensive sites. Local stone forms much of the construction, with limestone from Hovedøya Monastery reused in the walls. The oldest masonry uses orthocercal limestone, while later work includes other local rocks and brick, including the Munk brick bond. Medieval, Renaissance, Baroque, Empire, Neo-Renaissance, and modern military buildings stand together as a layered historical complex.
The medieval castle
Castle walls and entrance passages
The medieval castle was built on a rocky spur. A ring wall followed the steep cliff toward the south and west, while higher walls defended the rising ground to the north and east. The original complex included Vågehalstårnet, Nordfløyen, Sydfløyen, Romeriksfløyen, Skriverstuefløyen, Fadeburet, Fruerstuefløyen, a forecourt, Knutstårnet, and Jomfrutårnet.
Jomfrutårnet was the medieval outer gate tower and principal entrance. Its lower passage retains slots for a portcullis and traces of the drawbridge. The entrance moved to the lower Stallgården area in the sixteenth century, after which Jomfrutårnet remained principally defensive. It originally stood about 15 metres high and was later raised by one storey under Christian IV. Most of the tower was demolished around 1750. The surviving medieval lower section was later raised by two storeys during restoration and connected with the royal mausoleum.
Mørkegang was an angled passage between Jomfrutårnet and Sydfløyen. Partly underground and protected by gates and portcullises, it ended in one of the castle courtyards. Its angle prevented the use of a battering ram. Lønngang ran above it through the approximately three-metre-thick walls toward Nordfløyen, probably with a branch to Vågehalstårnet, and served as a concealed internal route for guards. Sections of both passages survive within the castle walls.
Nordfløyen and Fadebursfløyen
Nordfløyen was founded around 1300 as the principal medieval building. It contained the royal hall, royal apartments, and accommodation for servants and guards. The lightning fire of 1527 destroyed its timber roof and floors, after which parts of the upper walls and gables were rebuilt and a new roof installed. The walls were rebuilt again in 1917, and the roof was reconstructed using a medieval model and the Munk brick bond. The former upper royal apartment is now called the Margarethasaal, while the first-floor hall received the name Olav V Hall in 1969.
Fadebursfløyen is a one-storey building between Nordfløyen and Vågehalstårnet, attached directly to the medieval rubble-stone wall. It probably housed the royal archive and valuables. Its cellar was used for coin storage and was known as Pengehatten, or “money hat.” The building burned in 1527. Its medieval cellar survives, while the present superstructure was designed by Arnstein Arneberg.
Vågehalstårnet and the women’s wing
Vågehalstårnet was the central medieval defense tower and originally stood about 20 metres high. The 1527 fire damaged it severely, its upper section was removed about thirty years later, and most of the remaining tower was demolished in the seventeenth century. Its original footprint and the division of the courtyard are marked in the paving, while only part of the lower eastern rubble-stone wall is medieval. Arnstein Arneberg reconstructed the present structure with an intentionally uneven parapet to indicate its incomplete height.
Fruerstuehuset, the women’s wing, stood between Vågehalstårnet and Sydfløyen. Christen Munk rebuilt it in stone after an earlier timber building had become vulnerable to fire and decay. The two-storey structure stood on the eastern castle wall and contained a cellar, a seventeenth-century storage area for oil and wine, and an eighteenth-century knights’ hall. The governor lived there from 1570 to 1636. After later deterioration and partial demolition, it was reconstructed during twentieth-century restoration. It now contains cloakroom, stair, sanitary, pantry, and preparation facilities.
Sydfløyen and the castle church
Sydfløyen was built around 1300. Its original entrance passed through Mørkegang into the cellar, and the pointed-arch passage retains traces of a former portcullis. Prison cells were installed above the passage around 1540. A church occupied the ground floor from the mid-sixteenth century and the whole level from 1578. The upper floor contained royal apartments and later the rooms of the Overhoffretten, now called Christian IV’s Hall. The upper walls were rebuilt between 1738 and 1740, two long barrel vaults were added in the cellar, and the wing was restored between 1920 and 1958.
The castle church occupies part of Sydfløyen. Christian IV remodeled it in the 1620s, and it was altered again between 1738 and 1742. Its altarpiece was designed by the master builder E. D. Haüsser. The church crypt contains the Royal Mausoleum, and the cellar below the church has a barrel vault.
Skriverstuefløyen and Romeriksfløyen
Skriverstuefløyen dates from around 1300 but was rebuilt above the medieval wall in 1638. It served administrative purposes. Remains of the inner Lønngang and its gate tower survive beneath the wing. The projecting stair structure Det dobbelte hemmelighet connected it with the queen’s apartments in Sydfløyen.
Romeriksfløyen was also built around 1300 and received an additional storey in 1633. Its medieval cellar contained a kitchen, and two blocked doors formerly led toward Vedhagen. The lower and upper floors later served as residential and working rooms for the governor. The National Archive occupied the building from 1841 to 1844. The upper floor is now the Romerikssaal, and an attic preparation kitchen serves Olav V Hall.
Knutstårnet and the northern defenses
Knutstårnet, formerly Kanniketårnet, was built around 1300 as a northern flank tower and originally reached the height of Nordfløyen. Its earlier name may refer to a chancellery or writing room. The tower was damaged in the 1527 fire, rebuilt, used as a prison, and converted into a powder store in 1637. A horse mill operated there from 1641. It was partly demolished around 1750 and later reduced to its foundations before being partially reconstructed without its original height.
Knuts kurtine connected Knutstårnet with Nordfløyen and Romeriksfløyen. It originally carried a wooden wall walk and included access from the Margarethasaal. A passage was cut through the curtain wall in 1754, when loopholes were also added.
Inner bastion fortress
The inner bastion fortress was created to shield the castle from artillery. Its principal works include Dronningens batteri, Kongens batteri, Det dobbelte batteri, Skarpenort, Kronprinsens bastion, Prins Carls bastion, Arkeligården, and associated curtain walls, casemates, ditches, and galleries. A casemate is a vaulted protected chamber used for guns, ammunition, or shelter. The fortress also uses tenailles, low angular works placed in front of a wall, and hornworks, advanced defenses with projecting wings and a central element.
Vedhagen and Stallgården
Vedhagen was a fortified kitchen yard west of Romeriksfløyen. It contained fuel storage, a slaughterhouse, and a small smokehouse. A temporary timber bulwark was erected there during the Kalmar War. In 1640 and 1641, it was replaced by an irregular stone-faced half-bastion known as the large redoubt in Vedhagen and now called Romeriks Bastion. Four guns were installed there from 1648.
Stallgården, formerly the forecourt, was a fortified yard north of Vedhagen. Its buildings included a laundry, bakery, stable, well house, and well. The well was cut about ten metres into the rock using alternating fire and cold water, a technique also used for a concealed passage toward Munkedammen. A well house with an octagonal roof was later built above it, and the present structure follows traditional models. The original buildings were removed in 1743 and 1744, and prisoners raised the present interior earthworks. Three eighteenth-century 12-pound bronze guns stand on the rampart beside Munkstårnet. They bear fragments from a German aircraft bomb that struck Akershus on 9 April 1940.
Jomfrugården and Munkstårnet
Jomfrugården is the inner part of a tenaille in front of Sydfløyen. Its western wall descends with the ground and contains stepped loopholes known as Jomfrugårdens Geværgalleri. The eastern part of the tenaille was reduced to make room for the royal mausoleum.
Munkstårnet was erected in 1559 by Christen Munk as a combined cannon tower and gate tower, replacing Jomfrutårnet as the main gate. It also guarded Jernporten. The original pointed roof was replaced by a flat gun platform with a parapet in 1628, and each of its three levels had four gun ports. Jernporten was bricked up around 1660. A powder magazine with a vaulted ceiling was installed in the tower in the early eighteenth century, and the Norwegian crown jewels were stored there in the nineteenth century.
The medieval Vanntårnet, or water tower, formerly stood where Munkstårnet now stands. It has not survived. One interpretation identifies it as a rainwater cistern, while another allows for a defensive tower above the cistern, but the structure’s original form remains uncertain.
Batteries and powder stores
Dronningens batteri, also called Store voll, was laid out with Kongens batteri in 1567. Its earthwork contains an old powder cellar and a well repaired on Christian IV’s orders in 1617. A passage through the rampart was created in 1648, collapsed, and was rebuilt in 1684. A vaulted passage to Det dobbelte batteri has existed since the 1780s, and two eighteenth-century 12-pound guns stand on the battery.
Kongens batteri contains a casemate from the 1580s beneath the rampart. Two southern gun ports protected the eastern side of the castle, and the casemate was strengthened with a pillar and two arches in 1610. An eighteenth-century rifle gallery survives to the north and east. Four English muzzle-loading guns dating from 1871 now stand on the battery.
Det dobbelte batteri was completed late in the seventeenth century above earlier curtain walls. Lower guns stood in a large northern casemate, while upper guns occupied the roof, including two 6-pound guns and six iron 12-pound guns. Its powder chamber and passages included the concealed gate called dobbelte Lønnporten. Alterations in 1967 and 1968 converted the battery into the Norwegian Resistance Museum and blocked one of the concealed gates.
Skarpenort and the western defenses
Skarpenort Bastion was built between 1593 and 1604 under Axel Gyldenstierne and Jørgen Friis, following designs by Isaac van Geelkerck. It was originally called Scherpenhoeck or Scherpenoort and later Escarpe du Nord. Two old 24-pound demi-cartauns displayed there were cast in Freiburg for the Elector of Saxony. They passed through Schleswig-Holstein and Copenhagen to Båhus, and were moved to Akershus after Båhus passed to Sweden in 1658. They were used during the 1716 siege and remain associated with ceremonial salutes.
Skarpenorts kruttårn, the Great Powder Tower, was built in 1657 as a three-storey rubble-stone powder magazine and gate tower. Two large vaulted passages and a smaller passage once led through it. The original southern gates are now blocked and replaced by smaller iron doors. The tower bears the monogram of King Frederik III and the date 1657. It lost its gate-tower function after a new gate was opened beside it in 1693.
Blykjeller was probably built around 1600 with Skarpenort Bastion. The partly buried rubble-stone building has a brick vault and may have served as a casemate or powder store, although its original function is uncertain. A vaulted passage connected it with Skarpenorts kruttårn from 1657.
Kronprinsens and Prins Carls bastions
Kronprinsens bastion is a regular bastion begun between 1593 and 1604. A stone bears the date 12 April 1618, probably marking a later construction stage. Its interior earthworks were removed around 1830 to make room for prison buildings. A casemate occupied the center, and buildings known as Majorens hus and Oberstens hus stood within the bastion. Oberstens hus burned in 1673.
Prins Carls bastion was built during the major fortification phase of 1616 to 1653. By the 1650s, it was complete as a flanking work against Munkstårnet. From 1625 to 1653, it contained a temporary main entrance to the castle before the eastern curtain gate was completed.
Arkeligården and Corps de Garde
Arkeligården lies behind Dronningens and Kongens batteri. Its earth fill masks sloping ground and covers the former northern ring wall and ditch, whose remains were identified by twentieth-century test drilling. The area contains the Corps de Garde, a Baroque building with an open columned hall built in 1754 as a guardhouse with an arrest cell. It was later used as a residence.
Outer fortress and military buildings
Gates, courtyards, and defensive works
Festningsporten is the present main entrance. The gate and bridge were completed in 1653 after earlier openings in the eastern curtain had been created and closed during periods of tension with Sweden. The gate bears Christian IV’s monogram and the date 1744, which commemorates later repairs. The bridge was renewed several times, including in 1848, and the former dam was drained in the nineteenth century. Nordre brohus and Søndre brohus stand beside it. Søndre brohus was designed by Otto Fougner as a financial and securities depot, while Nordre brohus served as a storage building for the post and naval administration.
Artilleribygningen, also called Det lange røde hus, was built in 1774 on the northern curtain wall. Its supports remain visible inside the building, and a former passage to a sortie gate survives as a blocked route marked by an iron door. Part of its western end was removed in 1834. The building later housed archives and offices and now contains an information center.
Kronprinsens kruttårn was built in 1755 as a single-storey powder magazine with a vaulted chamber. A second storey was inserted in 1830 for fifty to sixty prisoners, and a third was added in 1853 with eight cells. Restoration in 1983 and 1984 marked the original profile. Nye Tenalje, built in 1750, was the last major defensive work of the fortress. Parts of the rock were blasted away and reused in its walls, which carry eighteenth-century 36-pound howitzers and 3- and 6-pound guns.
Hornverk and Kontraskjær
Hornverk was begun in 1657 and completed in 1689. It originally contained two earth-covered casemates with timber roofs. They were filled in during the eighteenth century and rediscovered in 1897. The western part was excavated and restored between 1974 and 1980. Høymagasinet on Hornverk was built in 1845 as a timber-framed hay store with brick-filled panels. Its advanced steel roof structure had originally been developed for Versailles railway station. The building was restored in the 1980s and now contains a model of Oslo.
Kontraskjær is a park on the former open ground between the city and the fortress. Earlier defenses included a zigzag ditch, covered way, counterscarp wall, and palisades, parts of which remain marked in the park. Foundations of a building burned in 1686 are visible. A riding ground and the Skansen restaurant were removed, and the terrain was reshaped to restore views toward the fortress. A transformer station and storage facility were built underground from the 1970s. Tony Smith’s steel sculpture Marriage stands in the park. Ridehus på Kontraskjæret, built in 1900 as a copy of the New Riding Hall, is used by the mounted police.
Prison and supply buildings
Store Provianthus was built around 1690 as a provisions store and extended twice in the eighteenth century. Around 1830, its windows and doors were moved from the east side to the west, and its structural system was probably altered to increase grain storage. The prison later used the building, and it housed the Army Museum from 1950.
Lille Provianthus was built in 1751 as a provisions store and converted into a prison in 1834. Dormitories, workrooms, cells, and extensions were added between 1838 and 1903. After the prison closed in 1952, the building became a training center and office building. Kornmagasin, built in 1787, was converted into a state prison from 1820. It could hold 150 prisoners and contained workrooms, dormitories, cells, a shop, and sickrooms. After repeated alterations following fires and later additions, it came to be used by the military police and royal guard.
Bakeri was built in 1759 to replace an earlier bakery. It originally contained four bread ovens, four grain-drying ovens, and four hand mills. It was later used as a shop, prison administration building, workshop, and office building. Restoration in 1998 and 1999 converted it into a training center.
Fengselkirke was designed by Heinrich Ernst Schirmer and Wilhelm von Hanno and completed in 1866. Its ground floor contained a prison kitchen and bath, while the upper floor held a chapel and training room. The building was converted to offices, a library, and training rooms in 1948, restored in 1968 and 1998 to 1999, and now serves as a training center for the Norwegian armed forces.
Kulegården and waterworks
Kulegården, also called Østre Voll, is level ground east of the castle beside Vågehalstårnet. Its surrounding walls were intended to prevent landslides rather than form a defensive line. A broad reinforcing wall called Den store pille was built in 1631. Buildings including Munkestuen and Hannibals dobbelte karnapp once stood there but were removed in the eighteenth century because the ground subsided. Later landslides led to further alterations in the 1980s.
The former garden east of the fortress included a pavilion, a deer, and, under Governor Jens Juel, a bathhouse. It was later replaced by a riding ground. Munkedammen was laid out in the eighteenth century beside the barracks as a water reservoir and was linked underground to the Stallgården well. It was restored in the nineteenth and twentieth centuries. Karpedammen forms part of an old watercourse that once flowed into Bjørvika south of Prins Carls bastion. It appears on fortress maps from the eighteenth century and was restored in both the nineteenth and twentieth centuries.
Military quarter and ceremonial ground
Barakker are soldiers’ barracks built in stages between 1747 and 1778 around Michael von Sundts plass. Part of the northern wing was later converted into prison cells and a main guardhouse. Since 1947, the complex has served as workshops, a shop, and offices. The Myntgatekvartal comprises Kavalleristallen, Ingeniørstallen, Artilleristallen, and Kavallerikasernen, with Offisersstallen and riding halls nearby. The brick buildings retain the character of a military and cavalry quarter, although many now contain offices.
Kavalleristall was built in 1867 and extended northward in 1894 and 1901 before conversion to offices in 1950. Ingeniørstall was built in 1897 and converted into a gymnasium in 1917, with an extension for changing rooms and air-force classrooms added in 1949. Artilleristall was designed by Schirmer and von Hanno and built in 1861 with a stable below and hay storage in the roof space. It was extended for cavalry in 1867 and became an administrative building after the Second World War. New windows and an additional floor were added in the 1950s.
Kavallerikaserne was designed by Ove Ekman in a simple Neo-Renaissance style and built in 1898 for the riding and squadron school. It was converted to offices after the Second World War. Offiserstall was built privately in 1891 by Henrik Nissen for officers. The state acquired it in 1930 for the army and riding school, and the mounted police used it again as a stable from 1972 to 1973 after earlier conversion to offices and a garage.
Oslo Militære Samfund was built in 1878 as a military association and clubhouse, with apartments for the caretaker, restaurateur, and intendant. A matching side building was added in 1940 beside Kronprinsens bastion. Festningsplass is a parade and ceremonial ground in Hovedtangen. It hosted royal receptions and announcements of heirs during the Danish-Norwegian period, was leveled as a parade ground in the nineteenth century, and remains in military ceremonial use. Norway’s National Monument, designed by Gunnar Jansson and unveiled by Crown Prince Harald on 8 May 1970, stands on its western side.
Administrative and support buildings
Materialgård was built in 1788 partly in brick-filled timber framing and partly in masonry. It contained an engineer’s residence, stores, and ancillary facilities, and a roofed Parade Hall was added in 1867. It now houses Forsvarsbygg offices. General Glads gård was designed by Johan Henrik Nebelong and built in 1844 for Lieutenant Colonel and commander Christian Glad. Its plastered brick construction and corner tower were inspired by medieval, partly German, castle architecture. The armed forces acquired it about thirty years later, and it now serves administrative purposes.
Kommandantskapet was designed by Patroclus von Hirsch and built around 1800 for the guard commander. This Empire-style, panel-clad house has a side wing that formerly contained a stable and laundry. Its original details are substantially preserved, and it continues to contain offices and the commander’s apartment. Festningens gymnastikksal was built in 1861 by Schirmer and von Hanno as a gymnasium and fencing hall. The Neo-Renaissance building has high plaster ceilings and a gallery. An extension was added in 1891 and raised by another storey in 1954 and 1955. Since the 1960s, it has housed the Norwegian Armed Forces’ data center.
Other documented buildings in the fortress area include the School Building, Army Depot, Quartermaster Workshop, Conference House, Incinerator House, Artillery Yard, Day House, New Riding Hall, Old Riding Hall, Main Gate Guardhouse, Military Band building, Workshop Buildings, Artillery Office Building, Southern, Central, and Northern Barracks, the Commandant’s Stable, Artillery Magazines, Arsenal Superintendent’s House, Main Arsenal, and Artillery Barracks.
