Ruins Ödenburg, castle ruins in Wenslingen in the canton of Basel-Landschaft, Switzerland

Ruins Ödenburg is a castle from the late 10th century sitting on a steep rocky outcrop high above the valley. The remains include wall foundations, a defensive walk, a strong tower, and several buildings made of stone and wood that show how people once lived there.

The castle was probably founded by the Counts of Homberg; their fief fell to Habsburg-Laufenburg in 1223, and the ruin is recorded in their possession in 1320. Finds show use from the late 10th to the late 12th century, and the site was abandoned around 1150 in the midst of a building phase, apparently for financial or political reasons rather than warfare. Excavations and restoration took place in 1941/42, 1968 and 1976–1979.

The original name is lost; because the overgrown ruin was simply called the "öde Burg" (desolate castle) in popular speech, that description became its name. The nearby villages Wenslingen and Tecknau are connected to the site by marked hiking trails, and the former gate can still be recognised by the pivot sockets of its two-winged door.

The site is easily reached from nearby villages with marked paths and a small parking area available. There are no food or overnight facilities on the grounds, so visitors should plan ahead and bring what they need.

Pottery and metalwork discoveries suggest the inhabitants were wealthy and lived with considerable comfort for their time. This tells us the site was more than just a military stronghold but also a well-appointed home for the ruling family.