Chefchaouen, or Chaouen, is a city in begin of the Rif Mountains of northwest Morocco. It’s known for the striking, blue-washed buildings of its old town. Leather and weaving workshops line its steep cobbled lanes. In the shady main square of Place "Outa el Hammam" is the red-walled "Kasbah", a 15th-century fortress and dungeon, and Chefchaouen Ethnographic Museum. The octagonal minaret of the Great Mosque rises nearby.

after this small definition
let's see top places to see if you come to chefchaouen.

Place Outa el Hammam ,the center of the old medina