Geography of Scotland example at Aberdeen. Much of the Scottish coastline consists of a machair formation, a dune pasture land formed as sea levels subsided. The east coast has several significant estuaries and other nature reserves including the Ythan Estuary and Fowlsheugh, both of which have been designated as Important Bird Areas. Firths of Scotland include the Solway Firth, Firth of Clyde, and Firth of Lorne on the west coast, and the Cromarty Firth, Moray Firth, Firth of Tay, and Firth of Forth on the east coast. The Pentland Firth is not an inlet, but the strait that separates the Orkney Isles from
Pentland Firth referring to the sea lanes of the entire west coast of Scotland down to Kintyre. One version of the 9th-century "Historia Brittonum" states that "the Britons originally filled the whole island with their peoples from the English Channel to the Sea of Orcs". On the Caithness (southern) side the Firth extends from Dunnet Head in the west to Duncansby Head in the east, while on the Orkney (northern) side from Tor Ness on Hoy in the west to Old Head on South Ronaldsay in the east. In the middle of the Firth are two significant islands, Stroma and Swona. The