Hexenturm, Medieval defense tower in Memmingen, Germany.

The Hexenturm is a rectangular defense tower in Memmingen with tuff stone at its base and brick construction in the upper sections, topped by a gabled roof. It stands on the northern edge of the old town district and forms a distinctive part of the medieval town wall.

The tower was built around 1150 during the city's founding period and served as one of three prison towers in medieval Memmingen's defense system. It played an important role in protecting and controlling the northern entrance to the city.

Whether the tower owes its name to the witch persecutions, because witches were said to be locked up here, is not known. The building is also called the Leaning Tower of Memmingen. The small house in front of it is used by the municipal works department as a tool shed.

The tower stands on the north side of the old town, between the Einlaß gate and the Hafendeckelturm. Its entrance is about five metres above ground, at the level of the old defensive walkway, so there is no ground-level door. The sandy subsoil has made the foundation yield to the northeast; a counter-foundation was added in the 20th century and steel cables now tie the tower to the Welfenhaus.

The tower is also called the "Leaning Tower of Memmingen": its sandy subsoil gives way to the northeast, and in the 20th century a counter-foundation was built and steel cables were anchored to the adjacent Welfenhaus to hold it. The small house in front of the tower now serves as a tool shed for the municipal works department.