Alcazaba is a big, old fort that was built a very long time ago in Spain. It's kind of like a castle with big walls and a lot of rooms inside. People used to live in the alcazaba a long time ago, and they would use it to protect themselves from bad guys.
The alcazaba has lots of towers that are really tall and make it easy to see all around. The towers also have little holes in them where people could shoot arrows at any bad guys who were trying to attack.
Inside the alcazaba, there are lots of little rooms where the people who lived there would cook and sleep and keep their things. There were also big rooms where they would have parties and hang out with their friends.
Nowadays, the alcazaba is very special because it's very old and has a lot of history. Lots of people come to visit it and learn about what life was like a long time ago in Spain.