Royal Geographic Society

Three from a set of five released for the Royal Geographical Society's 150th anniversary. Top right shows the Braaid Circle, hypothesized to be first a stone circle, then subsequently built up and used as walls for a Norse farmstead. Issued: February 5 1980.
Above is the Neolithic chambered cairn of Cashtal-yn-Ard. It has been excavated twice in the last century.