Trier, Germany's oldest town, lies in a basin in the Mosel valley. Its importance in ancient times is attested by impressive Roman remains such as are found nowhere else north of the Alps. Numerous churches reflect its long-established status as the see of a bishop.
During the summer months there are excursion ships on the Mosel (sometimes sailing as far as Luxembourg) and the Saar.
Southeast of the Trier Hauptmarkt, in Konstantinplatz, are the Episcopal Museum and the Aula Palatina, a Roman basilica built in the time of the Emperor Constantine (who resided in Trier from 306 to 312), now restored and used as a church (Protestant). Adjoining is the old Electoral Palace (Kurfürstliches Palais; 17th and 18th C.), now occupied by local government offices.
To the east of the Trier Hauptmarkt stands the Cathedral (Dom; fourth, 11th and 12th C.; restored 1964-74), one of the oldest churches in Germany. Magnificent monuments of the 16th-18th centuries; rich treasury, including the portable St Andrew's Altar (10th C.), one of the great masterpieces of Ottonian art.
From the Porta Nigra in Trier, Simeonstrasse (pedestrian zone; Dreikönigenhaus, ca. 1230) runs southwest to the Hauptmarkt, with St Gangolf's Church (Late Gothic) and the Steipe (1430-83), the old banqueting house of the city councilors. A little to the west, in Dietrichstrasse, is the Frankenturm (11th C.), one of the earliest surviving dwelling houses in Germany.
9km/6mi southwest of Trier, on the left bank of the Mosel, lies the village of Igel, with the Igel Column, a funerary monument 22m/72ft high, with rich carved decoration, belonging to a Gallo-Roman family of the third century.
To the south of the palace in Trier, beyond a stretch of the medieval town walls which bound the palace gardens (Baroque sculpture), can be found the Rhineland Museum (Rheinisches Landesmuseum), with a collection of antiquities and works of art of prehistoric, Roman, Early Christian, Frankish and medieval times.
Northeast of the Porta Nigra, in Paulinstrasse, is St Paulinus's Church (by Balthasar Neumann, 1732-54; ceiling paintings by Thomas Scheffler), one of the finest Baroque buildings in the whole of the Rhineland.
From the Imperial Baths in Trier, Olewiger Strasse runs east to the Roman Amphitheater, built about AD 100, which had seating for some 25,000 spectators.
The Basilica in Trier was originally the throne room of the Emperor of Constantine. Later it became the fortified castle of the Prince-Electors of Trier.
Always closed on: New Year's Day (January 1), Day after Christmas, St Stephen's Day, Boxing Day (December 26), New Year's Eve (December 31), Christmas - Christian (December 25), Christmas Eve - Christian (December 24)
South of the Trier Electoral Palace are the ruins of the Roman Imperial Baths (Kaiserthermen; fourth C.; converted into a fortified castle in medieval times; extensive complex of underground rooms and passages), one of the largest bathing establishments of Roman Imperial times. From here the Südallee leads west to the Barbarathermen (second C.). The nearby Römerbrücke over the Mosel still rests on Roman foundations.
40km/25mi southwest of Konz by way of Saarburg and Remich is the little town of Nennig, with the remains of a Roman villa discovered in 1852. The villa's mosaic pavement, measuring 10.30m/34ft by 15.65m/51ft, is one of the largest and finest mosaics north of the Alps.
On the southern outskirts of Trier stands the 12th C. pilgrimage church of St Matthias (with the remains of the Apostle Matthias), belonging to a Benedictine house (re-founded 1907) on the site of an Early Christian building.