Once the main hall of the imperial residence built by Constantine in 310, the imposing structure was modified many times before finally recovering its original form in the 19C. Rebuilt in 1954, the basilica is now a Protestant church.

The Rhineland museum has a prehistory section as well as a particularly rich collection of Roman antiquities. Superb mosaics and bronze statuettes dazzle the eyes, but the Neumagen ship sailing down the Moselle laden with wine is one the most spect..

The treasury of the municipal library contains a collection of precious and illuminated manuscripts: medieval gospels, Bibles, old documents, treaties and safe conduct passes.

The northern gate to the walled town dates from the 2C and owes its name to the dark patina that covers the sandstone blocks. The gateway was designed for military use: assailants who forced their way through the outer gates would find themselves in ..

These baths date from the time of Constantine and are among the largest from the Roman era, although they look as they have never been used. The baths comprised the caldarium (hot baths), the tepidarium (tepid water baths) and the frigidarium (cold w..

The most interesting exhibits here are the 4C frescoes of the palace of Constantine, discovered under the cathedral. The first floor is reserved for sacred art. Note the original sculptures from the west façade of the church of Our Lady.

The cathedral looks more like a fortress than a church. Its massive and austere façade with its squat rounded towers is a fine example of Early Romanesque architecture. The essentially Baroque interior contains interesting altarpieces. The south aisl..

This church was directly inspired by one in the Champagne region of France, with the ground plan in the form of a Greek cross. There are thus four apsidal chapels, between each pair of which two smaller, three-sided chapels have been interposed, givi..

The market cross stands in the middle of the square. It was erected in 958 when the town was granted the right to hold a market and was restored in the 18C. The fountain, with its painted figures, dates from the 16C. From the square, admire monuments..

The house of the Tree Kings is a Gothic-style town house with arched windows reminiscent of the Italianate towers of the patricians of Regensburg.

Tall windows illuminate the austere single nave of this church designed by Balthazar Neumann and completed in 1754. The martyrdom of St Paulin and members of the Theban Legion in 268 is illustrated in the paintings on the ceiling. Rococo stuccowork d..

This Roman arena on the side of a mountain could seat up to 20 000 spectators and was used as a quarry in the Middle Ages. By the 18C it had become so damaged that vines were grown on the terraces.

Only the north and east wings remain of the former Renaissance electoral castle dating from 1615. The Rococo wing was built from 1756 to 1762. Its magnificent staircase is one of the most beautiful creations of its kind in Germany. The French-style p..

This massive tower built in about 1100 is pierced with small windows. Although not contemporaneous with the Franks, the tower no doubt takes its name from the fact that the town fell into Frankish hands at the end of the 5C.

The municipal museum in the convent of St. Simeon presents collections of models, furniture and paintings that recount the history of the town. The nearby cloister has been converted into a lapidary museum.

The birthplace of Karl Marx has been transformed into a museum. It contains information concerning his life and work, first editions and translations of his major works, Das Kapital etc.

These 2C baths of St. Barbe remained in service for several centuries but are now in ruins.