Megaliths
A megalith is a large stone that has been used to construct a structure or monument, either alone or together with other stones. The word "megalithic" describes structures made of such large stones, utilizing an interlocking system without the use of mortar or cement, as well as representing periods of prehistory characterised by such constructions. For later periods the term monolith, with an overlapping meaning, is more likely to be used.
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