Théatre gallo-romain de Thénac, Roman theatre ruins in Thénac, France

The Théâtre gallo-romain de Thénac is a theatre-with-arena of at least 84 m diameter, its cavea facing east, built in small local Campanian limestone on flat ground. The orchestra and lower cavea rest on the slightly hollowed bedrock; the perimeter wall is held by semi-cylindrical buttresses turned inward against the earth fill, and five radiating vomitoria divide the seating into six cunei. Today a curved earthen bank and lawn mark the spot.

The theatre belonged to a rural sanctuary 5 km south of Saintes (Mediolanum Santonum), between two ancient roads linking that city to Bordeaux, alongside a spring and baths. Its architecture suggests construction under Nero. It was less used from the late 2nd century but stayed in service until at least the third quarter of the 3rd century, then served as a stone quarry. Partly excavated in 1825-1828 by René Eschassériaux, it was classified as a monument historique on 18 December 1990 and has belonged to the commune since 2000.

The name "Arènes" comes from the arena form of this theatre, whose wide, slightly horseshoe-shaped orchestra of 46.20 m was suited to shows other than classical drama. Two rows of seats next to the orchestra seem reserved for dignitaries. Many iron nails found on the site suggest wooden stands and a wooden stage building.

The theatre stands on flat ground, not a hillside: its orchestra and the lower part of the cavea rest directly on the limestone bedrock, which was slightly hollowed out. The upper cavea is filled with earth and held by internal buttresses, so the visible bank is a modern landscaped earthwork. The remains are the property of the commune of Thénac since 2000.

The cavea's perimeter wall is held by semi-cylindrical buttresses turned inward, a device also found at Augst and Vieux-la-Romaine, built to resist the thrust of the earth used as fill in the upper part of the monument. Five radiating vomitoria cut into the cavea divide it into six cunei.