On the way back home we visited Trier (French: Trèves; Luxembourgish: Tréier; Spanish: Tréveris; Latin: Augusta Treverorum). It is a city in Germany on the banks of the Moselle River. It is the oldest city in Germany, founded in or before 16 BC by the Roman emperor Augustus.

Trier lies in a valley between low vine-covered hills of ruddy sandstone in the west of the state of Rhineland-Palatinate, near the German border with Luxembourg and within the important Mosel wine-growing region.

Trier is the oldest seat of a Christian bishop north of the Alps. In the Middle Ages, the Archbishop of Trier was an important ecclesiastical prince, as the Archbishopric of Trier controlled land from the French border to the Rhine. He was also one of the seven electors of the Holy Roman Empire.