Callanish Stones in Western Isles

You're standing at the Calanais Stones, on a low ridge above Loch Roag on the west coast of the Isle of Lewis. Start with the middle. That tallest stone is almost five metres high, yet only about thirty centimetres thick. It's shaped like a ship's rudder and probably weighs around seven tonnes. Historian Burl reckons it took about thirty people to raise it. Around it stand thirteen stones in a ring, about three metres tall on average. It isn't a perfect circle, by the way: the east side is slightly flattened.