Saints-Geosmes appeals to travellers who want to get to know a place through its architectural history and military past. The Église des Trois-Jumeaux brings together several distinct building phases and a crypt beneath the nave; Fort de la Bonnelle represents Langres’s former defensive system. The town’s local connections also offer a practical perspective.

The Église des Trois-Jumeaux and its architectural history

The present-day Église des Trois-Jumeaux was built at the end of the 12th century on the remains of an 8th-century basilica. It was modified in the 18th century. When placing it in its historical context, it is important to distinguish between the earlier building and the present-day church: the basilica dates to the 8th century, while the present-day church dates to the late 12th century. The 18th-century modifications mark a further building phase. This gives a sequence of an earlier building, construction of the present-day church and later modifications.

Beneath the present-day nave is a three-aisled crypt with a semicircular apse. “Three-aisled” describes its division into three aisles; the apse is the semicircular part at the end. Its position beneath the nave makes the crypt a distinct architectural focal point within the church.

The heritage protection also applies to specific parts of the building: the crypt was protected on 7 September 1892, and the rest of the church on 9 July 1909. The two dates therefore do not refer to the same part of the building. Anyone interested in the church’s history can consider its building phases and protection history separately: one tells the story of the earlier building and later modifications, while the other records the different protection dates for the crypt and the rest of the church.

Fort de la Bonnelle: its former defensive role

Fort de la Bonnelle was an outwork of Langres’s former defensive system. It lay between Fort du Cognelot and Fort de la Pointe du Diamant. Its role was to monitor the south of Langres and the Langres–Dijon axis. The two neighbouring forts help to place it within the defensive system, while the areas it monitored make its strategic role clear.

Construction began shortly before the Franco-Prussian conflict of 1870. The fort was completed in 1885, following revised plans by General Séré de Rivières. The start and completion dates mark different stages in its construction history: work began shortly before the conflict and was completed in 1885. The revised plans were also part of this development.

Visits to the fort are possible only by prior request to the municipality of Saints-Geosmes. As visiting arrangements may change, confirm them with the municipality in advance. Suitable walking shoes, warm clothing and electric torches are recommended for your visit.

Voie verte and getting around the town

The Voie verte in Saints-Geosmes improves the connection between residential areas and the business park. This adds practical information about the town to its historical themes: the focus here is not on a single building, but on the connection between residential and business areas. These offer different perspectives to consider when planning your stay—the church and fort as historic sites, and the Voie verte as a route within the town.

Discover more destinations

Discover more destinations: Viéville, Bourbonne-Les-Bains, Dancevoir, Culmont, Bugnières, Fayl-Billot, Chaumont, Châteauvillain.

For the overview of the wider region: Haute-Marne.