Civitas Popthensis was an ancient Roman-Berber city located in the present-day Henchir Kssiba area in the municipality of Ouled Moumen in Souk Ahras Province, Algeria.

Initially the "Civitas Popthensis" was probably a big village at the centre of an opulent agricultural land with cereal, olive growing, as many presses and livestock have been found in and out of the city.

Civitas Popthensis was located at the foot of the "Alpes Numidicae" and near the present border between Tunisia and Algeria [3] Its period of maximum prosperity seems to be at the beginning of the 3rd century, under emperor Septimius Severus.

From the area ruins and the evaluation of the flow of water, Julien Guey, a French archeologist, estimated the population of the agglomeration around 10,000 and 12,000 inhabitants.

Excavations in the 1930s resulted in the foreground the religious history of the city by finding a sacred area and 47 steles dedicated to Saturn.