The Ta' Hagrat Megalithic Temple is the oldest megalithic temple in Malta since it was the first one to be built. It is much older than the British temple of Stonehenge! What now mainly remains of this megalithic temple is its 'Trilithon Entrance'.

A mound of earth through which blocks of stone emerged was excavated by Prof .Zammit in 1925 - 1927 on the site know as Ta' Hagrat (which in English means "made of stones"), at the entrance of the village of Mgarr (Mgarr lies about 15km to the west of the capital, Valletta) in a field in front of the government school.

The ruins consist of two groups of buildings. The building, with the main SE-NW axis, consists of a slightly concave front about 15m wide with a well- constructed gateway in the middle. Two steps lead up to a corridor flanked by large hardstone uprights on which.originally,horizontal slabs were laid to cover part of the entrance. The two hardstone slabs are 2.7 and 2.4m long respectively.

The corridor in front of the entrance, 5m long, is paved with large stone blocks ; at the end is a paved rectangular space surrounded by large slabs on end. Laterally, on each side, a doorway leads to an elleptical chamber or apse (room) built of roughly squared blocks. The one on the west shows a thick curved wall built on the south, which reduces the chamber very considerably; the one to the east has its apsidal end intact but the northern wall is completely removed. In front of the rectangular space, is a circular room 4m in diameter; its walls are made of roughly- hewn blocks of stone. In plan, this part of the building has the appearance of a three-lobed figure, like the ace of clubs on a playing card.

The smaller building to the north is entered form the larger building, through the eastern apse. This smaller building is made of stones but the trefoil arrangement (made up of three semi-circular apses) was retained. Pottery, flints implements, and other objects characteristic of the Stone Age, were obtained in considerable quantity.