The town museum is located in the former Augustinian monastery. The church tower, parts of the east wing with a late Gothic chapel, remains of the west wing and the cloister are still preserved from the original Gothic complex.

The Augustinian monastery was founded in 1280 by the town's lord Günther von Salza. It existed until 1539 and was then dissolved. The tower of the former monastery church can be climbed as part of the museum tour. From there, there is an interesting view of the preserved monastery complex and the historic town center of Bad Langensalza. The rooms on the ground floor of the east wing of the former dormitory of the monastery have been preserved. The municipal museum in Langensalza was opened on June 27, 1900 with an exhibition commemorating the Battle of Langensalza in 1866 and has since developed into a town museum with a wide range of exhibits.