Hydra is a commune in the province of Algiers, Algeria. It is located in Bir Mourad Raïs district, in the plateau of western Algiers, the wealthier part of the national capital. It was heavily affected during the 11 December 2007 Algiers bombings.

Algiers Province is a province (wilayah) in Algeria, named after its capital, Algiers, which is also the national capital. It is adopted from the old French department of Algiers and has a population of about 8 million. It is the most densely populated province of Algeria, and also the smallest by area.