Teufelsturm, Medieval watchtower in Menden, Germany.

Teufelsturm is a round stone tower with thick walls, to which a half-timbered house was added in 1700. This structure combines the medieval fortification with living spaces added later.

The tower was built by the mid-14th century during the planned fortification and reconstruction of Menden under Elector Walram, though its offset from the 14th-century wall line suggests it may belong to an earlier, 9th-century defensive circuit around the Vincenzkirche. Menden's fortifications were dismantled from the mid-18th century, but the Teufelsturm survived alongside the Poenigeturm and Rentschreiberturm. In the early modern period it held people accused of witchcraft, and around 1700 a half-timbered house was added.

The tower houses a carnival museum that displays how regional carnival traditions form an important part of local celebration and community identity.

The tower stands off the line of the 14th-century wall, set back from the street; the half-timbered annexe added around 1700 marks the entrance side. The carnival museum inside is run by the Menden carnival society Kornblumenblau, which restored the building between 1978 and 1981, so visits depend on the society's opening arrangements rather than fixed daily hours.

The tower's name Duivelsturm probably dates from the witch trials, when accused people were held inside it. It stands noticeably offset from the line of the 14th-century town wall, which suggests it belonged to an older, smaller fortified enclosure around the Vincenz-Kirche, possibly going back to the 9th century.