Regensburg

Regensburg is a city in eastern Bavaria, Germany, built at the confluence of the Danube, the Naab and the Regen, where the Danube reaches its northernmost point. It is the capital of the Upper Palatinate subregion of the state and, with more than 150,000 inhabitants, is the fourth-largest city in Bavaria after Munich, Nuremberg and Augsburg and the eighth-largest on the Danube. The city began as an imperial Roman river fort and grew into the political, economic and cultural centre of the surrounding region. Under the Holy Roman Empire it hosted the Perpetual Diet of Regensburg, and in English it was long known as Ratisbon. Its medieval centre, the biggest medieval city site north of the Alps, was made a UNESCO World Heritage Site in 2006 for its well-preserved architecture and its importance as a meeting place of imperial assemblies. Its climate straddles the humid continental and oceanic zones of the Koppen classification.