Château du Frankenbourg: A Historic Fortress in Neubois, France

Visitor Information

Google Rating: 4.7

Popularity: Low

Country: France

Civilization: Celtic, Early Modern, Medieval European

Site type: Military

Remains: Castle

History

The Château du Frankenbourg stands on the Schlossberg mountain near Neubois, France. Its origins trace to early Celtic and Roman settlements before developing into a medieval stronghold built by Frankish rulers.

Long before the castle’s medieval phase, the site was occupied during the late Bronze Age and Iron Age, evidenced by fortified enclosures known as “pagan walls” typical of the La Tène culture. The area shows traces of Celtic habitation followed by Roman presence, as revealed by coins from the imperial period, including one issued under Emperor Constantine I, and other artifacts such as a bronze axe and a figurine shaped like a bull. These findings suggest continuous occupation and strategic importance through ancient times.

According to tradition, the fortress was founded in the 5th century by Clovis I, the first King of the Franks, who named it Frankenbourg, meaning “Fortress of the Franks.” Legend has it that Clovis built a chapel on this site and that it was near here, during the Battle of Tolbiac, where he converted to Christianity. Although these stories have symbolic value, the earliest concrete references to Frankenbourg date much later.

The first documented mention of the castle appears in a charter from 1123 issued by Emperor Henry V. During the High Middle Ages, it was controlled by the Counts of Frankenbourg, a family related to the Counts of Saarbrücken and later the Counts of Werd. The castle was held as a fief of the Bishopric of Strasbourg, reflecting its role within the ecclesiastical and feudal structure of the region.

Over the following centuries, ownership passed through several noble families such as the Counts of Werd and the Linange or Leiningen lineage. By the late 15th century, the Strasbourg Cathedral Chapter and the city of Sélestat had acquired the castle, marking a shift in administrative control from aristocratic to ecclesiastical and municipal authorities.

In 1582, a lightning strike caused a devastating fire that destroyed significant parts of the castle. Although it was rebuilt afterward, the fortress gradually fell into disuse and ruin by the 17th century. Recognizing its historical value, the ruins were declared a historic monument in 1896. Further protection was extended to the older surrounding prehistoric walls in 1990, reflecting ongoing efforts to preserve the full archaeological legacy of the site.

Remains

The Château du Frankenbourg consists mainly of the remains of a large rectangular enclosure atop the sandstone ridge of the Schlossberg. Its medieval walls, which vary between six and ten meters in height, form a polygonal shape that adapts to the natural rock formation. The main entrance faces north toward the Alsace plain, protected by a 16th-century triangular tower designed to guard the gate.

One of the most prominent surviving structures is the bergfried, or defensive tower, positioned on the north side near the Val de Villé. Built around the mid-13th century, this tower rises eleven meters and features exceptionally thick walls measuring four meters. Its vaulted interior is constructed from brick and has been carefully restored in 1981, making it one of the best-preserved components of the castle.

Within the courtyard on the southern side, remains of a stone staircase comprising twenty to twenty-five steps have endured, likely granting access to the first floor of an internal building. Near this southern entrance, a small window partially obscured by debris still provides views over the Lièpvrette valley, suggesting defensive or observational purposes.

Extending below the medieval fortifications along the west slope of the mountain lies the “pagan wall,” an ancient enclosure dating from the late Iron Age, sometimes attributed to the La Tène period. This massive wall encircles roughly 1.7 hectares and is made of large stone blocks joined with dovetail-shaped joints—a complex technique indicating significant craftsmanship. The wall measures about 1.8 meters thick and between 0.6 to 0.9 meters in width and stands between 0.5 and 0.7 meters tall in its best-preserved sections. Archaeological evidence, including Celtic and Roman coins and brooches known as fibulae, supports its use during multiple eras, possibly ranging from the Celtic through the early medieval period.

Within the castle’s enclosure, archaeological studies have revealed remains of residential buildings situated toward the west side, as well as a 12th-century bastion on the southern edge. These elements illustrate the castle’s expansion and adaptation over time to evolving defensive needs.

Since the 1970s, local historical societies and hiking groups have undertaken efforts to clear, stabilize, and conserve the fortress ruins. These activities, along with the significant restoration of the bergfried, have helped preserve both the medieval architecture and the older prehistoric fortifications, ensuring the site’s historical layers remain accessible for study and appreciation.