The Callanish (or Calanais in Gaelic) Standing Stones is a complex of 50 stones in a cruciform arrangement roughly aligned north-south, with an inner circle of 13 stones and a small chambered cairn. They date from 3000BC and there are several other prehistoric sites nearby, including 3 additional circles. As with other stone circles in Britain, there is no satisfactory explanation for the purpose of these monuments - though, according to tradition they are petrified giants.

There is a modern visitor centre managed by Urras nan Tursachan (The Standing Stones Trust).