Megalithic Monuments of Alcalar, Archaeological site in Mexilhoeira Grande, Portugal.

The Megalithic Monuments of Alcalar form an archaeological complex with eighteen burial structures spread across a hilltop on the limestone coast of the Algarve. The tombs vary in design, featuring stone-built corridors and central chambers that once held human remains and burial goods.

This burial complex dates back to the third millennium before our era and stands among the earliest known burial sites in southern Portugal. The construction methods reveal that prehistoric communities possessed advanced knowledge of stone building and spatial organization.

The name Alcalar, like Alcalá, comes from Arabic. Excavations in the 1990s showed the tombs served as ossuaries where the dead were buried in a fetal position. Only the community's most influential members were placed here, with ivory, amber, copper, gold and green stone ornaments, some materials brought from far away.

The site lies near Mexilhoeira Grande, about 9 km from Portimão, off the Municipal Road 532. The interpretative centre, inaugurated in 2000, was closed for rehabilitation in 2012; check locally before relying on it. Monuments 7 and 9 are on a marked visit route, but the ground is uneven, so wear sturdy shoes.

Tholos 7 has a 27-metre diameter and an east-facing entrance whose limestone slabs narrow the passage to the chamber, which sits at the geometric centre of the tomb. Its base is built of schist and repeated in an outer wall that forms a pathway around the mound.