Coetan Arthur dolmen, also known as Arthur's Quoit (not to be confused with Carreg Coetan Arthur, near Newport) is the remains of a Neolithic burial chamber (also known as a quoit). It dates from around 3000 BCE. The site, situated on the hillside close to St Davids Head in Pembrokeshire, Wales, is the collapsed chamber of what is presumed to be a passage grave which also has a round barrow. The massive capstone measures approximately 6 metres by 2.5 metres and is supported on one side by an orthostat approximately 1.5 metres in height.
References:The Broch of Clickimin is a large and well preserved, though somewhat restored broch near Lerwick. Originally built on an island in Clickimin Loch (now increased in size by silting and drainage), it was approached by a stone causeway. The water-level in the loch was reduced in 1874, leaving the broch high and dry. The broch is situated within a walled enclosure and, unusually for brochs, features a large 'blockhouse' between the opening in the enclosure and the broch itself. Another unusual feature is a stone slab featuring sculptured footprints, located in the causeway which approached the site. Situated across the loch is the Clickimin Leisure Centre.