A policy for the protection of cultural and natural heritage sites was adopted by Unesco in 1972

Since then its world heritage committee has compiled a list of 855 “properties” around the world that it believes have “outstanding universal value”

In Britain, 27 of these range from those of great natural beauty, such as the Giants Causeway in Northern Ireland, to historic buildings

Some of these buildings are steeped in ancient history, such as Maeshowe and Skara Brae on Orkney. Others are of more recent vintage, including New Lanark in Scotland

None receives statutory protection, but some are protected by local bylaws and planning regulations.

Among the first UK sites to achieve world heritage status were the Welsh castles of Harlech and Beaumaris. These were described by Unesco as “extremely well-preserved monuments” to the “colonisation” achieved by Edward I

St Kilda was the first Scottish site. Recognised for its outstanding natural beauty and for the vestiges of its population, which lasted for 2,000 years until 1930, when it was evacuated

The most recent British addition is the mining landscape in Cornwall and West Devon

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