Answer:
A megalith is a prehistoric refuge made with one or several stone blocks, large and unworked. The term comes from the Greek words mega , large and lithos , stone.
The megalithic adjective describes stories structures, whose construction was done with an interlocking system that does not use mortar or cement. It has been used to describe buildings built by people from different parts of the world and from different eras. A wide variety of large stones have been identified as megaliths, the majority being non-funeral use, perhaps raised with religious fines, such as memorials or territorial markers. Among the best known megaliths are dolmens, menhirs and cromlechs.
In Europe the construction of these structures began, mainly, in the Neolithic (although examples of the initial Mesolithic-Epipaleolithic were found), as part of the transformations that accompanied the Neolithic agricultural revolution, being extended during the Chalcolithic and Bronze Age. Large megalithic monuments are scattered throughout much of Western Europe, but the most important foci are in Brittany, southern England and Ireland, and southern Spain and Portugal.
