The Xerez Cromlech (Cromeleque do Xerez) is a megalithic structure of standing stones (menhir) around one central stone. The site has been reconstructed since the stones had to be moved to keep them from being submerged by the Alqueva reservoir. They have been placed in a quadrangular shape instead of a circle, which is unusual. Construction is estimated to have taken place sometime between the early 4th to mid-3rd millennium BC. The site is located near Monsaraz, Portugal.