A menhir is a large upright standing stone. Menhirs may be found singly as monoliths, or as part of a group of similar stones. Their size can vary considerably; but their shape is generally uneven and squared, often tapering towards the top. Menhirs are widely distributed across Europe, Africa, and Asia, but are most numerous in Western Europe; in particular in Ireland, Great Britain and Brittany. In northwest France there are 1,200 menhirs. They originate from many different periods across pre-history, and were erected as part of a larger Megalithic culture that flourished in Europe and beyond.
The function of Menhirs has provoked more debate than practically any other issue in European pre-history. Over the centuries they have variously been thought to have been used by Druids for human sacrifice, used as territorial markers or elements of a complex ideological system, or functioned as early calendars. Until the nineteenth century, antiquarians did not have substantial knowledge of prehistory; and their only reference points were provided by Classical literature. The developments of radiocarbon dating and tree-ring calibration have done much to further human knowledge in this area.
The word menhir was adopted from French by 19th century archaeologists. It is a combination of two words found in the Breton language; men (stone), and hir (long). In Modern Welsh they are described as maen hir, or "long stone." In modern Breton, the word peulvan is used.
Practically nothing is known of the social organization or religious beliefs of the people who erected the menhirs. We have no trace even of these peoples' language; however we do know that they buried their dead, and had the skills to grow cereal, farm, and make pottery, stone tools, and jewelry. Identifying their uses remains speculation. However, it is likely that many uses involved fertility rites and seasonal cycles. Until recently, menhirs were associated with the Beaker people, who inhabited Europe during the later third millennium BC; the European late Neolithic and early Bronze Age. However, recent research into the age of megaliths in Brittany strongly suggests a far older origin, perhaps back to six to seven thousand years ago.
Many menhirs are carved with megalithic art. Images of objects such as stone axes, ploughs, shepherd crooks and yokes were common. With the exception of the stone axe, none of these motifs are definite, and the name used to describe them is largely for convenience. Some menhirs were broken up and incorporated into later passage graves where they had new megalithic art carved with little regard for the previous pictures. It is not known if this re-use was deliberate or if the passage grave builders just saw menhirs as a convenient source of stone (Le Roux 1992).In many areas, standing stones were systematically toppled by Christians; of the many former standing menhirs of northern Germany, scarcely one stands today.