Thermae in Xanten

The Colonia Ulpia Traiana’s public baths stand on Insula 10, a city block near the Roman centre of Xanten. They covered about 11 500 square metres and enclosed an inner courtyard ringed by colonnades, shops, latrines, a water tower and an entrance hall. Marble linings and carved facades gave the rooms a grand appearance, and the complex served as the city’s social hub. Archaeologists first uncovered parts of the building in 1880–82, but its purpose was only recognised in 1928 by Paul Steiner. After mid-20th-century excavations and factory demolition, a glass-and-steel canopy was built in 1999 to protect the ruins. Since 2008 the RömerMuseum’s upper floor leads visitors over the exposed remains of frigidarium, tepidarium and caldarium, each supplied by nine ovens whose volcanic stone cladding still stands. Beyond the heated rooms lies a nearly equal-sized palaestra, a sunlit exercise court framed by colonnades. At the north-west corner a water tower held the 244 cubic metres of fresh water needed daily for baths, fountains and latrines. Nearby, the smaller Herbergsthermen on Insula 38 served overnight guests, their restored heating system still demonstrating how a single fire warmed both water and floors.