The Guelma Roman Baths, a classified site since 1998, go back to the Roman era, to the 2nd century AD, located in the interior of the Byzantine castle (the old military base). Some portions of the Roman baths are still standing.
The Baths are a structure of polished stones of varying sizes, resting on stone pillars, and consisting of different rooms grouped around a large rectangular hall (22 m long and 14 m wide), which can be reached by a small staircase. There are four water reservoirs on site to supply the baths. There are archways from the main doors and chains on the walls, as well as marble pieces and carvings depicting a half-statue, a falcon and a three-pronged sceptre with winged dolphins.
This location witnessed one of the most horrific massacres of 8 May 1945, committed by the French army against defenceless Algerians, where mass executions of peaceful protesters took place.