Trier

Trier is Germany's oldest city and Rome's northern capital, and it does not let you forget either fact. Augusta Treverorum served emperors — Constantine ruled the West from here — and the survivals are staggering: the Porta Nigra, the mightiest Roman city gate north of the Alps, black with age and intact to its upper galleries; the Imperial Baths and amphitheatre; the Roman bridge still carrying traffic on second-century piers; and Constantine's Basilica, the emperor's audience hall — the largest surviving single-room structure of antiquity, its bare brick vastness now a Protestant church whose organ fills Roman air. Together with the cathedral, which guards the Holy Robe relic above a Roman core, the ensemble is UNESCO heritage of the first rank.

The Middle Ages made Trier an electoral capital; the nineteenth century gave it a different world-historical son: Karl Marx, born 1818 in a baroque house on the Brückenstrasse that is now a thoughtful museum of his life and afterlives.

Between monuments flows the Mosel, and with it the city's true daily religion: Riesling from the world's steepest vineyards, poured in wine taverns that have measured Trier's twenty centuries by the glass. Antiquity concerts in the baths and amphitheatre, the theatre's season and the Mosel Music Festival complete a city where every stone has already heard everything — and stays to listen again.