The Roman baths of Riez are a set of two thermal complexes from the Roman era. They are found on the southern bank of the Colostre"), in the current city of Riez, in the department of Alpes-de-Haute-Provence. Their remains were excavated in the years 1966 to 1972, but they disappeared during real estate operations, and are now barely visible.

The discovery made in 1842 in the cathedral area by Benjamin Maillet of square masonry and praefurnia (heating systems) was not studied in depth at the time because the commission in charge of evaluating his work did not consider it necessary. It was not published, and the only trace of the discovery is the handwritten notes in Maillet's notebook. Some archaeological work carried out in 1936 by Jules Formigé") in the same sector only provided modest results. We will have to wait for the excavations carried out between 1966 and 1972 by Guy Barruol") to exhume the remains of the cathedral baths glimpsed by Maillet, as well as those of the eastern baths.[1] Finally, the investigations directed by Philippe Borgard (CNRS Center Camille Jullian) from 2003, combine the exploitation of the drillings from the previous excavations with specific drillings, and make it possible to partially reconstitute the organization of the two thermal complexes.[2] Less than 200 m separate the two complexes, located on both sides of the Valvachère stream, a small tributary of the Colostre.[3]​.

Discovered in 1842, and excavated starting in 1966 within the framework of a study of the remains of the early Christian cathedral, which reveals its implementation on the substructures of the baths, leveled at about 25 cm to serve as foundations for the cathedral.[4] These baths are the ones with the best restored organization. They were built on an artificial terrace protruding from the canalized course of the Valvachère. This terrace is 74 meters long and about 30 meters wide. A 3.45 meter wide portico formed the façade of the baths along the Valvachère. Behind this portico three wings can be reconstructed distributed in a U shape around a courtyard: the large northern room is 11.25 meters wide and has no intermediate walls, making it a gymnasium "Gymnasium (Ancient Greece)"). Its floor is tiled concrete. The west wing is divided into four rooms, three of which have a hypocaust (heating system). The fourth, the northernmost, in the northwest corner, serves as a link between the gym and the three heated rooms. This is the cold room, the . Its strong masonry suggests that it was a vaulted room. At its western end there is a swimming pool. The other three rooms constitute the hot part of the thermal baths and should be interpreted as the (the steam room), which is accessed through the preceded by the apoditerium (cloakroom and vestibule of the thermal complex). The wing is only partially excavated, which does not allow its functions to be reconstructed. Only the beginning of two rooms was discovered.[5]​.