Speyer, Germany

Founded by the Romans around 10 BC, Speyer sits on the Rhine in Rhineland-Palatinate and counts roughly 51,000 residents. Its 1030 Speyer Cathedral, the largest Romanesque church in the world at 134 meters long and a UNESCO World Heritage Site since 1981, holds the burials of eight Holy Roman Emperors and German kings. The 1526 Diet of Speyer granted princes the right to choose their religion, and the 1529 Protestation at Speyer gave Protestants their name, a moment commemorated by the 1830 Memorial Church. A 1090 mikveh ranks among the oldest Jewish ritual baths in Europe, while the 1990 Technik Museum displays a Boeing 747 mounted on a pole.