Walk the length of the wall that protected Ancient Messene, a structure considered to be a model of military architecture. In places, lying deep in vegetation or emerging above the trees, this 3m-thick stone structure snakes over a course of 9.5km. It is punctuated by several towers, which housed the garrisons and between which there are massive gates. The Arcadia Gate, 2km from Mavromati, is the best preserved, and presents two entrances separated by a vast circular courtyard.