Eday is one of the islands of Orkney, which are located to the north of the Scottish mainland. One of the North Isles, Eday is about from the Orkney Mainland. With an area of , it is the ninth largest island of the archipelago. The bedrock of the island is Old Red Sandstone, which is exposed along the sea-cliffs.
There are various well-preserved Neolithic tombs, as well as evidence of Bronze Age settlement and the remains of a Norse-era castle. During the period of Scottish rule the substantial property of Carrick House was developed at Calfsound, which became a burgh for a short period. During the British era many agricultural improvements were introduced, although there has been a substantial decline in the population since the mid-nineteenth century. In the twenty-first century the Eday Partnership has had success in promoting the island's economy. Local placenames reflect the diverse linguistic heritage and the landscapes of the island and its surrounding seas attract abundant wildlife.
==Geography and geology==
Eday is long from north to south but only just over 500 metres wide at the narrow neck of land between the Sands of Doomy and Bay of London〔 and has been described as being "nipped at the waist".〔Hewitson, Jim "The North Isles" in Omand (2003) p. 185〕 The centre of the island is largely moorland covered with heather, and cultivation is confined to the coasts.〔Haswell-Smith (2004) p. 387〕
The highest points are Flaughton Hill at the island's centre, Fersness Hill at West Side, Vinquoy Hill to the north and Ward Hill to the south, which reaches .〔 In Orkney this last name, which derives from the Norse ''varði'', is a common one for the highest point on an island as in the past they were used for lighting warning beacons.〔("Orkney Placenames - natural elements" ) Orkneyjar. Retrieved 15 July 2007.〕
The largest body of fresh water is the Mill Loch, south east of Vinquoy Hill.〔("Sites of Special Scientific Interest (SSSI): Mill Loch" ) Orkney Islands Council. Retrieved 1 April 2012.〕 Loch of Doomy lies on the western side of the narrow "waist" and the smaller Loch Carrick on the north coast.〔
The population is dispersed along the coastal farmsteads and nowhere on the island has the status of a village. Calfsound is the most populous of the settled areas, with other concentrations at Millbounds on the east coast, which has a post office and a community facility in a converted chapel, and Backaland in the south where the ferry from the Mainland docks.〔
Eday is surrounded by other small islands that make up the "seemingly impossible green and russet jigsaw of Orkney's North Isles".〔 Calf of Eday lies to the north of the settlement of Calfsound. Further east is Sanday across the Eday Sound. Stronsay and Linga Holm are to the south east and Muckle Green Holm to the south west beyond the straits known as the Fall of Warness. Egilsay lies some due west. Rusk Holm, Faray and Holm of Faray lie beyond the Sound of Faray to the north west and beyond them is the larger island of Westray.〔
In common with its neighbouring isles, Eday is largely formed from Middle Devonian Old Red Sandstone deposited in the Orcadian Basin. The Eday Group is the name for a substantial sequence of sandstones that is found at many locations in Orkney, for which Eday and the area around Eday Sound are the type area. In places it is up to thick, and is largely composed of yellow and red sandstones with intervening grey flagstones and marls.〔Hall, Adrian and Brown, John Flett (September 2005) ("Upper Middle and Upper Devonian Sediments" ). "Orkney Landscapes". Retrieved 4 Mar 2012.〕 The rock is easily quarried and some of the yellow sandstones from Fersness were used in the construction of St Magnus Cathedral in Kirkwall.〔〔Tait (2005) p. 474〕 The Devonian sequence is deformed into a major fold, the north-south trending Eday Syncline, with the youngest part of the sequence, the Upper Eday Sandstone outcropping in the north of the island from Bay of Cusby to Red Head. The oldest part of the sequence, the Rousay Flagstones are found on the eastern side of the island at Bight of Milldale and from Kirk Taing to War Ness, and to the west from Sealskerry Bay to Fersness. Veness is formed of Upper Eday Sandstone downfaulted against the flagstones.〔Mykura, W. (with contributions by Flinn, D, & May, F.) 1976. British Regional Geology: Orkney and Shetland, Institute of Geological Sciences, Natural Environment Council, 149pp.〕
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