Radbrunnenturm (Wheel Well Tower)

The Radbrunnenturm houses a well that reaches 41 m deep into the rock. It was operated with a treadwheel, which is where the Radbrunnenturm gets its name from. Today, an art center is located within the walls of the Radbrunnenturm.
Source: breisach.net/rundgang/rundgang-07-02-radturm-1.htm

The city's first town hall was located in the Radbrunnenturm. It has been rebuilt several times over the centuries.

In 1198, Duke Berthold V of Zähringen had the 41 m deep drinking water well built. The shaft was driven through the rock of the Münsterberg to below the level of the Rhine and served as the central water supply for the upper town, even during sieges. It is assumed that there was already a shaft for drawing water at this point. The first tower above the well was 54 m high. Until 1847, a wooden treadwheel was used to pump water, after which a mechanical pumping station took over this task. From the beginning of the 13th century, the building, which housed a council chamber, was also Breisach's first town hall. To the north of the tower, a courtroom with a torture chamber and prison cell was added. This is also where the "painful interrogation" of the notorious governor Peter von Hagenbach took place in 1474. Destroyed in the Revolutionary Wars in 1793, the tower was rebuilt in 1826 with a height of 15 m. After the pumping station was taken out of service in 1902, the tower served as a residential building. In the course of Breisach's reconstruction after the Second World War, the building was raised to 34 m in 1953 during the term of office of Mayor Josef Bueb. Since 1982, the "Radbrunnen Breisach Art Circle" has used the tower as an exhibition and concert space. The Radbrunnen tower is also important during carnival; the original fool is excavated here. On the southeast side of the tower at the main entrance on the left are old stone tablets, and on the right is a Gothic pillory column. On the opposite northwest side of the tower there is both a historical monument, the Hagenbach-Türmle, and a modern work of art, the Radbühne.
Source: de.wikipedia.org/wiki/Radbrunnenturm