Burg Kalden, Medieval castle ruins in Altusried, Germany

Burg Kalden is a castle ruin sitting on a hill above the Iller River in a village in Bavaria. The location is protected by steep ravine walls on one side, and a round tower roughly 6 meters in diameter remains standing.

A noble family named Callindin is recorded here in 1128, serving the monastery of Kempten. The older castle, Alt-Kalden, was destroyed before 1500 by landslides on the unstable slope. Joachim von Pappenheim built Neu-Kalden 300 metres to the south in 1515; it was sold to the princely abbey of Kempten in 1692 and abandoned at once because of the risk of slipping ground, then demolished around 1840 down to one tower fragment. Altusried bought the ruin in 1985.

The castle shows building traditions of Bavarian noble families, with its round tower made from stones available in the area. This choice of materials still shapes how the ruins look today.

Visiting requires a short walk up the hill with steep sections and uneven ground. The site is accessible year-round, but paths can be slippery after rain.

The ruins display layers of gravel, sand, and marl that show how erosion influenced medieval building methods. These geological patterns are still visible in the ruins today.