?? Oldest German city & Porta Nigra - Sightseeing in Trier

Trier is the oldest city in Germany, founded by the Celts in the late 4th century BC. The German philosopher Marxism founders Karl Marx was born here. Porta Nigra is a must see in Trier. It is the Oldest, still existing Roman gate that you can find. The also called Black gate was built by the Romans at the end of the 2nd century. Only this gate is still existing and it is a World Heritage Site.