Aachen Cathedral, frequently referred to as the "Imperial Cathedral" (in German: Kaiserdom), is a Roman Catholic church in Aachen, Germany. The church is the oldest cathedral in northern Europe and was known as the "Royal Church of St. Mary at Aachen" during the Middle Ages. For 600 years, from 936 to 1531, the Aachen chapel was the church of coronation for 30 German kings and 12 queens.
Charles the Great (Charlemagne) began the construction of the Palatine Chapel around 792, along with the building of the rest of the palace structures. It was consecrated in 805 by Pope Leo III in honour of the Virgin Mary. It was extensively renovated in the 10th century and restored in 1881. The core of the cathedral is the Carolingian Palatine Chapel, which is notably small in comparison to the later additions.