Concentric stone circle

A stone circle is a monument of standing stones arranged in a circle. Such monuments have been constructed in many parts of the world throughout history for many different reasons. Outside of Europe, stone circles have also been erected, such as the 6300~6900 BCE Atlit Yam in Israel and 3000~4000 BCE Gilgal Refaim nearby, or the Bronze Age examples from Hong Kong.

The best known tradition of stone circle construction occurred across the British Isles and Brittany in the Late Neolithic and Early Bronze Age, with over 1000 examples still surviving to this day, including famous examples like Avebury, the Rollright Stones and Stonehenge. Another prehistoric stone circle tradition occurred in southern Scandinavia during the Iron Age, where they were built to be mortuary monuments to the dead.

The size and number of the stones varies from example to example, and the circle shape can be an ellipse.

All experts agree that stone circles are of pre-Christian date, but beyond that stone circles have proven difficult to date accurately. Radiocarbon dating has produced a wide range of dates at different sites. This is at least partly due to an inadequacy of materials suitable for radiocarbon dating that can be reliably obtained from the sites. The diversity of radiocarbon evidence may also suggest that stone circles were constructed over a very long period, or were sometimes reconstructed at later dates. It is often not clear when building started. A further obstacle to dating is that there are generally no other archaeological artifacts associated with the stone circles. Traditional archaeological artifacts, such as pottery sherds, bones, etc., are not often found at the sites, and when found are frequently of a later date than the associated stone circle.

The sites display no evidence of human dwelling, and rarely encompass graves. This suggests that stone circles were constructed for ceremonies (perhaps religious ceremonies) and were in use on ceremonial occasions only. The type of ceremonies (if any) is entirely unknown. An alternative hypothesis is that they were a form of amulet or talisman, i.e., an entity acknowledging and appeasing supposed spirits dwelling in nature, meaning that their ceremonial use was secondary to their talismanic value, or equal to it. The crudeness and variety of the stones excludes the possibility that they had astronomical observation purposes of any precision. Sometimes a stone circle is found in association with a burial pit or burial chamber, but the great majority of these monuments have no such association. A stone circle is an entirely different entity from a henge, and different also from an isolated monolith, yet sometimes these other types of ancient stone monuments are found in close proximity.

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Wikipedia