The Archangel Michael Thassos Monastery is a convent of the 13th century. Located between the villages of Astris and Aliki and is built on the edge, above a wild cove, with spectacular views, both for those facing away from and for those of its windows overlook the sea.

In the monastery kept a piece of the Holy Nail, ie part of the nails that crucified Christ, while very rich is the showroom of. To visit the monasteries are required to observe dress code etiquette, and clothing for those who have not adequately prepared, offered at the entrance.

According to religious tradition, he Saint Luke hermit and sanctify the Monastery of the Archangel Michael, while some argue that it was he who originally built the old church on the 1110.