The major works undertaken between 1817 and 1830 transformed the citadel of Algiers into a most important place of sovereignty and power, boasting different administrative, economic and religious centres. However, today, the physiognomy of the surroundings of this palace-fortress is marked by the upheaval of the French colonial period between 1830 and 1870.
In the Ottoman regency, the fortifications of Algiers evolve according to the politico-economic growth experienced by the city partly thanks to the development of the maritime piracy and the lusts it entails. Its stranglehold on the sea, arouses many projects of punitive expeditions. The construction of fortifications is then the major concern of its new leaders who between the sixteenth and the seventeenth centuries, fortify the city, its bay and the hinterland.