and enslaved its inhabitants. The Ketchaoua Mosque (Djamaa Ketchaoua جامع كتشاوة), at the foot of the Casbah, was before independence in 1962 the cathedral of St Philippe, itself made in 1845 from a mosque dating from 1612. The principal entrance, reached by a flight of 23 steps, is ornamented with a portico supported by four black-veined marble columns. The roof of the nave is of Moorish plaster work. It rests on a series of arcades supported by white marble columns. Several of these columns belonged to the original mosque. In one of the chapels was a tomb containing the bones of Geronimo. The building seems a curious blend of Moorish and Byzantine styles. Algiers possesses a college with schools of law, medicine, science and letters. The college buildings are large and handsome. The Bardo Museum holds some of the ancient sculptures and mosaics discovered in Algeria, together with medals and Algerian money. The port of Algiers is sheltered from all winds. There are two harbours, both artificial—the old or northern harbour and the southern or Agha harbour. The northern harbour covers an area of . An opening in the south jetty affords an entrance into Agha harbour, constructed in Agha Bay. Agha harbour has also an independent entrance on its southern side. The inner harbour was begun in 1518 by Khair-ad-Din Barbarossa (see History, below), who, to accommodated his pirate vessels, caused the island on which was Fort Penon to be connected with the mainland by a mole. The lighthouse which occupies the site of Fort Penon was built in 1544. Algiers was a walled city from the time of the deys until the close of the 19th century. The French, after their occupation of the city (1830), built a rampart, parapet and ditch, with two terminal forts, Bab Azoun باب عزون to the south and Bab-el-Oued اد to the north. The forts and part of the ramparts were demolished at the beginning of the 20th century, when a line of forts occupying the heights of Bouzareah بوزريعة (at an elevation of above the sea) took their place. Notre Dame d'Afrique, a church built (1858–1872) in a mixture of the Roman and Byzantine styles, is conspicuously situated overlooking the sea, on the shoulder of the Bouzareah hills, to the north of the city. Above the altar is a statue of the Virgin depicted as a black woman. The church also