Blida lies surrounded with orchards and gardens, 190 metres (620 ft) above the sea, at the base of the Tell Atlas, on the southern edge of the fertile Mitidja Plain, and the right bank of the Oued el kebir outflow from the Chiffa gorge.

The abundant water of this stream provides power for large corn mills and several factories, and also supplies the town with its numerous fountains and irrigated gardens.

Blida is surrounded by a wall of considerable extent, pierced by six gates, and is further defended by Port Mimieh, crowning a steep hill on the left bank of the river.

The center of a fertile district, and a post on one of the main routes in the country, Blida has a flourishing trade, chiefly in oranges and flour.

[2] It was intricately rebuilt of interconnecting alleyways and streets, and was made accessible through the existing six major gates.

The Berbers of Blida are known as Djebailia and have been in the plains of Blida/Matija for thousands of years according to historians such as Ibn khaldoun.