The Groined vault at Markt 15 is a fragment of a tower with paintings from the 16th century. In 1988/1989, there were two old houses on the current site. One of them was a farmhouse with a threshing floor and galleries on the second floor. In the entrance area, there was a living room and kitchen on the south side and storage and cellar rooms on the left. After the death of the former owners, the houses were to make way for new apartments. Demolition work began in 1988, without anyone suspecting that the front left-hand section contained a real gem. After clearing out a storage room, construction workers noticed that there was an opening to a cellar in the floor of the room. They also noticed fragments of paintings under peeling plaster and a striking vaulted ceiling. They suspected that this might be something special. The construction company and client informed the relevant authorities and the demolition was halted. Unfortunately, it was already too late for the farmhouse. An examination of the room revealed that it was a fragment of a tower with a groined vault. Closer examination revealed paintings from the 16th century hidden under several layers of paint. The object was classified by the Thuringian State Office for Monument Preservation and Archaeology as a historically significant monument and the paintings were found to be unique in Thuringia. The building fragment itself consists of a barrel-shaped basement with a door opening on the north side and a bricked-up window on the south side. The first floor is almost square with a later, non-load-bearing groined vault. A source from 1861 reports of a monastery courtyard in Bad Tennstedt, which belonged to the Gotha Augustinian monastery. Around 1482, 20 monks are said to have lived there. There is also a report of a tenancy agreement in which the farm was handed over to a Hans Frawen for life in 1499. He was given the task of continuing to house the passing monks and maintaining the building. When the site was redeveloped in 1995, the tower fragment was painstakingly integrated into a residential and commercial building. In 2009, graduate restorer Ms. Suzy Hesse began uncovering the whitewashed paintings during a practical semester at the Erfurt University of Applied Sciences. It turned out that the entire vaulted room was covered with pictorial and floral representations. The paintings were applied to various plaster surfaces. The main theme of this painting is the depiction of the cycle of Queen Esther from the Old Testament. The complete painting of the room dates back to 1575, as can be seen from two dates on a wall and above the entrance door. The restoration work was completed in 2014.