The city is built upon the declivity of a steep hill, about three miles south-east of Cape Caxine. Its general form presents a triangular outline, and the houses being all white it has the appearance of a sail when seen from a distance at sea. One side is on the bay, the walls on the other two sides extend up the hill from the water's edge; they are about thirty feet in height and twelve in thickness, built of brick, with towers at intervals, and a shallow ditch on the outside. At the place where these walls meet, is situated the Casauba or citadel, an octagon fort separated from the houses of the town by a deep moat, and which has served since 1817 as the treasury and palace of the Dey. About a mile south-east of the Casauba on a hill completely commanding the city, was a square castle of brick, mounting sixty guns, called the Kallahai or Emperor's Castle, which name it derived from occupying the spot where Charles the Fifth pitched his tent. Two other forts situated near the shore, one north of the city called Akoleit, and the other south called Babazon, mounting about thirty guns each, completed the fortifications of the place on the main land as they existed in 1816. They were of little importance in a military point of view, being intended principally to keep the inhabitants in order; they however served as effectual protections against the attacks of the Arabs and Kabyles. The whole circumference of the town does not exceed a mile and a half, and there are scarcely any suburbs, the ground around the walls being devoted to cemeteries and gardens. The houses are closely built, the streets being with one or two exceptions narrow tortuous lanes, many of them covered over: the mosques, bazaars and public buildings are generally inferior in size and style. The population has been variously estimated, but the researches made by the French since their capture of the place, show that it has never exceeded fifty thousand, including the Turkish garrison, the number of which varied between seven and ten thousand. The defences on the sea side were indeed formidable. Opposite and eastward of the city, at the distance of two hundred and fifty or three hundred yards was a little island, from which the place derives its name _Al Gezeir_ or _the island_; it has been however connected with the main land by a solid causeway of stone, and the whole together forms a continued mole. The space of sea opposite the city thus partially enclosed by the mole is the harbor, which opens directly to the south, and does not exceed seven acres in extent. On the mole are the offices and magazines of the marine department which are surrounded by fortifications, mounting at that time two hundred large guns and fourteen mortars.