Stiftskirche Lahr, Gothic church in Lahr/Schwarzwald, Germany

Stiftskirche Lahr is a five-bay, three-aisle early Gothic basilica with a narrow choir bay, a choir ending in five-eighths and straight-ended side chapels continuing the aisles. The west facade and recessed tower were rebuilt in 1877 reusing the Gothic portals; the nave arcades have pointed arches on square piers with half-columns, and the rib vaults rest on plate-shaped bases linked to the Strasbourg Cathedral workshop.

Founded in 1259 by Walter von Geroldseck next to his castle as a hospital chapel, the church converted from a monastic institution to a secular foundation in 1482. This shift reflected changing social needs in the region.

The name "Stiftskirche" recalls the secular collegiate foundation into which the monastery was turned in 1482; the church has been the parish church since that year. Since 1558 it has belonged to the Protestant Kreuzgemeinde Lahr. On the cemetery, numerous historic gravestones are preserved.

The church stands east of the former settlement, in today's urban area of Lahr. The west facade and its recessed tower were rebuilt in 1877, reusing the Gothic portals; the medieval buttresses survive on the choir and on the four eastern bays of the north side. The interior is a five-bay basilica, with the choir closed on five sides and straight-ended side chapels.

The organ is by Orgelbau Mühleisen, built between 1966 and 1972, and renovated and enlarged in 1997; it has 50 stops on four manuals and pedal. In the churchyard, numerous historic gravestones survive. The ribs of the side-aisle vaults run level, while those of the nave rise, and the disc-shaped projecting bases point to the Strasbourg Cathedral workshop.