Roman baths of Badenweiler, Roman archaeological site in Badenweiler, Germany

The Roman baths of Badenweiler are the remains of a bathing complex built into the slope north of the present Cassiopeia Therme. In its final phase it measured at least 93 by 33 metres, with two symmetrically arranged bathing rooms, each holding a pool of about 60 square metres and one metre deep, plus changing rooms with apses and foot basins.

Construction began in the 1st century AD starting with two pools and later expanded into a full bathing complex with reception and changing areas. The site reflects Roman settlement and development in this region.

The site was dedicated to Diana Abnoba, a local goddess identified with the Roman Diana; an altar and a sandstone fragment bearing her name were found in the apses of the changing rooms. Three Celtic coins found here show that the thermal springs were already in use before the Romans arrived.

A glass roof protects the site year-round, allowing visitors to examine the ruins in all weather conditions without getting exposed to the elements. On-site displays explain Roman bathing practices and what daily life looked like at this complex.

Natural hot springs with temperatures around 26 degrees Celsius supplied water to the complex without needing artificial heating. This natural heat source was the main reason the Romans built a bathing facility at this location.