Houmt Souk meaning literally "The Market neighborhood", is a commune and the main town of the island of Djerba, Tunisia. A popular tourist destination, it is best-known for its traditional souk (market) and the Aghlabid fortress. It is located at approximately 20 kilometers from Ajim and 22 kilometers from El Kantara by the Roman road. It is also the chief town and a municipality with 64,892 inhabitants. The city itself shelters a population of 44,555 inhabitants as of 2004. The city developed on the old site of a Roman city called Gerba or Girba which had the honor of giving birth to two Roman Emperors, Trebonianus Gallus and his son Volusianus.
The city as it is today developed on the site of an ancient Roman city called Gerba or Girba, which shared its name with the island. Many besides the Romans lived there, including Numidians, Punics, Arabs, Spanish, and Turks; the town was also home to many merchants and pirates for many years. The Battle of Djerba took place in the northern part of the city. Close to the fort is a large village which served as a market; cattle and woolen cloth were traded there, as were dried grapes. Under the French protectorate (1881–1956) the island was divided into twelve sheikhates. French soldiers entered the town on July 28, 1881, and it remained a garrison until 1890, when its administration passed to civil French authority. In 1956, upon Tunisian independence, it became the capital of Djerba.