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Local architecture

There are many public buildings of interest, including the whole Kasbah quarter, Martyrs Square (Sahat ech-Chouhada ساحة الشهداء), the government offices (formerly the British consulate), the " Grand ", " New ", and Ketchaoua Mosques, the Roman Catholic cathedral of Notre Dame d'Afrique, the Bardo Museum, the old Bibliothèque Nationale d'Alger —a moorish palace built in 1799–1800 and the new National Library, built in a style reminiscent of the British Library.

The main building in the Kasbah was begun in 1516 on the site of an older building, and served as the palace of the deys until the French conquest. A road has been cut through the centre of the building, the mosque turned into barracks, and the hall of audience allowed to fall into ruin. There still remain a minaret and some marble arches and columns. Traces exist of the vaults in which were stored the treasures of the dey.

Djamaa el Kebir (Jamaa-el-Kebir الجامع الكبير) is the oldest mosque in Algiers. It was first built by Yusuf ibn Tashfin, but reconstructed many times. The pulpit (minbar منبر) bears an inscription showing that the building existed in 1097. The minaret was built by the sultan of Tlemcen, in 1324. The interior of the mosque is square and is divided into aisles by columns joined by Moorish arches.

The New Mosque (Jamaa-el-Jedid الجامع الجديد), dating from the 17th century, is in the form of a Greek cross, surmounted by a large white cupola, with four small cupolas at the corners. The minaret is 27 metres (89 ft) high. The interior resembles that of the Grand Mosque.

The church of the Holy Trinity (built in 1870) stands at the southern end of the rue d'Isly near the site of the demolished Fort Bab Azoun باب عزون. The interior is richly decorated with various coloured marbles. Many of these marbles contain memorial inscriptions relating to the British residents (voluntary and involuntary) of Algiers from the time of John Tipton, the first English consul, in 1580 (NB Some sources give 1585). One tablet records that in 1631 two Algerine pirate crews landed in Ireland, sacked Baltimore, 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 95 hectares (235 acres). 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 396 metres (1,299 ft) 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, 3 km (2 mi) to the north of the city. Above the altar is a statue of the Virgin depicted as a black woman. The church also contains a solid silver statue of the archangel Michael, belonging to the confraternity of Neapolitan fishermen.

Villa Abd-el-Tif, former residence of the dey, was used during the French period, to accommodate French artists, chiefly painters, and winners of the Abd-el-Tif prize, among whom Maurice Boitel, for a while of two years. Nowadays, Algerian artists are back in the villa's studios.