Derbent Fortress, Military fortress in Derbent, Russia.

Derbent Fortress is a military fortification in Derbent with two parallel walls stretching from the Caspian Sea toward the Caucasus Mountains. The complex includes 73 defense towers, multiple gates, and the Naryn-Kala citadel at its highest point.

Persian Emperor Khosrow I commissioned the fortress in the 6th century as a defense against nomadic invasions from the northern steppes. Later empires expanded and modified the structure, leaving layers of construction from different periods.

The fortress shows building elements from Persian, Arab, and Russian periods, including ancient baths, a palace, and one of the oldest mosques in Russia. Visitors can see these different eras directly when exploring the structures within the walls.

Visitors can enter the complex through nine remaining gates and explore the various areas on their own. It is best to allow time for climbing to the citadel and walking along the walls, as there are many sections to see.

The fortress remained in continuous military use for over 1500 years, making it one of the longest-functioning defensive structures in the world. This extended service means visitors can see layers of defense techniques from different eras all in one place.