"A ghorfa (Arabic: غرفة room) is a Berber architectural term used to describe a vaulted room used for storing grain. Ghorfas are often stacked as multi-story structures, sometimes reaching four stories high. Traditionally, ghorfas were grouped together as a ksar, a fortification used by Berber villages in North Africa to store large amounts of grain. Ghorfas were featured prominently in the film Star Wars: The Phantom Menace as the slave quarters of Mos Espa, home to Anakin Skywalker. These scenes in the film show ghorfas from several locations in southern Tunisia, including Ksar Ouled Soltane and Ksar Hadada." http://en.wikipedia.org/wiki/Ghorfas
When we went to Southern Tunisia in 2007, we visited some ghorfas, the architecture of the vaulted rooms for storing grain are really quite unique.