Mistras
My favorite place of the trip! Mistras is a fortess-church complex built on the top of a large hill outside Sparta, which is now a pretty po-dunk town. The citadel has been occupied by the Turks, the Greeks and the Arabs. There are dozens of churches dotting the hill on the long, but gorgeous, walk down (several hours), many with frescoes from the 12th century - a major feat, considering that frescos have a nasty tendency to pull away from the wall and shatter on the ground!