Guelma, town, northeastern Algeria. It lies on the right bank of the Wadi el-Rabate just above its confluence with the Wadi Seybouse. Originally settled as pre-Roman Calama, it became a proconsular province and the bishopric of St. Possidius, biographer and student of St. Augustine. Among the town’s Roman ruins are baths and a theatre, and 5 miles (8 km) west, at el-Announa, are the remains of Thibilis. Parts of the Byzantine walls still encircle the town, and the museum and the public gardens contain Roman relics and epigraphy. The modern town was founded by Governor Bertrand Clauzel in 1836 as a French military base.
Enclosed by mountains rising to nearly 2,000 feet (610 metres) and covered by olive groves, the town is laid out in the French style of wide, tree-shaded streets, with the Casbah and military quarters to the south and the Arab quarter to the west. Although it has some light manufacturing (chinaware, bicycles, motorcycles, and small motors), Guelma is mainly an agricultural centre with a large cattle market, giving its name to an Algerian breed. The noted spa of Hammam Meskhoutine (“Bath of the Damned”), 12 miles (19 km) west, has the hottest waters known (208 °F [98 °C]) after the Iceland geysers. Pop. (1998) 108,734; (2008) 120,004.