Ksar of Ait-Ben-Haddou

The ksar, a group of earthen buildings surrounded by high walls, is a traditional pre-Saharan habitat. The houses crowd together within the defensive walls, which are reinforced by corner towers. Ait-Ben-Haddou, in Ouarzazate province, is a striking example of the architecture of southern Morocco. [source]

I haven’t been here (yet).