Zähringen Castle

The ruins of Zähringen castle is what remains of the ancestral seat of the Zähringer Alemannic noble family, located near Freiburg im Breisgau.The Zähringer became a powerful ducal dynasty in the area of what is now South Germany and Switzerland in the high medieval period and the founder of several cities, including

Freiburg im Breisgau, Villingen, Neuenburg, Freiburg im Üechtland, Bern, Thun, Rheinfelden and Murten.

The name Zähringen is mentioned for the first time in records dating back to the early 11th century.

Source: Wikipedia