The kasbah is a unique kind of medina, or Islamic city.

It was the place for the local leader to live. It served also as a defense when the city was under attacks. It had high walls, which usually had no windows. Some times, they were built on the top of hills to make them easier to defend. Some of them were also placed near the entrance of harbours.

Having a kasbah built was a sign of wealth of some families in the city. Almost all cities had their kasbah, being this building something necessary for the city to survive. When colonization started in 1830, in northern Algeria, there were a great number of kasbahs that lasted for more than 100 years.

The word casbah has a slightly different meaning.