However this may be, during the 12th century the elector of Trier took the title of archchancellor for the kingdom of Arles, although it is doubtful if he ever performed any duties in connexion with this office.
The next three years he spent at Trier, which he chiefly made his headquarters, organizing the defence of the Rhine frontier, and personally superintending the construction of numerous forts.
Trier contains more important Roman remains than any other place in northern Europe.
The most remarkable Roman building in Trier is the Porta Nigra, the north gate of the city, a huge fortified gateway, 115 ft.
The most famous of the relics preserved in the cathedral is the "Holy Coat of Trier," believed by the devout to be the seamless robe of the Saviour, and said to have been discovered and presented to the city by the empress Helena.