Standing stones. These are the Standing Stones of Stenness, located on the Orkney Islands to the north of Scotland. They date from around 3000 BC (during the neolithic or New Stone Age). Only four of the original twelve stones remain. The tallest stone is 6 metres high. The stones once formed an ellipse (flattened circle). It is thought that the stones formed part of a ceremonial complex, with a structure in the middle that might possibly have been an altar. One of the stones was the legendary Odin Stone, but this was uprooted in 1814. It was later used in a mill and eventually destroyed by someone who was unaware of its ancient history.