The menhir is the simplest megalithic structure — a vertically standing stone, sometimes reaching 20 meters in height. The purpose of menhirs has not yet been established, though some archaeologists believe they were connected with burial rites. There is also a view that these stones were raised to mark some important date, or as boundary markers. These stones are scattered across the whole world — of various heights, single or in groups. They occur in Europe, Africa and Asia, but most of all in western Europe. They were erected in various periods of prehistory and form part of the great megalithic culture that flourished in Europe and beyond. According to recent data, menhirs date back 7,000 years.