Humans have inhabited Orkney, an archipelago in the north of Scotland, for about 8,800 years: Archeological evidence dates from Mesolithic times. Scandinavian clans dominated the area from the 8th century CE, using the islands as a base for further incursions. In the late 14th century the archipelago became part of Scotland. Prehistoric Orkney As with Prehistoric Scotland generally, hunter gatherers followed the slow retreat of ice age glaciation. The rapid spread of Neolithic culture up the western seaways soon brought early farming settlements and Megalithic culture. The prevalent use of the local sandstone, found ready split into convenient building slabs on the shore, preserved numerous structures from this period, including prehistoric villages, brochs, souterrain structures, chambered cairns and standing stones. The oldest stone house still standing in northern Europe (occupied from 3500 BC to 3100 BC) is at Knap of Howar on the island of Papa Westray, with walls intact to a low eaves height, and stone furniture looking very usable. Finely made and decorated Unstan ware pottery links the inhabitants to chambered cairn tombs nearby. At Skara Brae on the Mainland, passageways connect similar houses into a village, dating from about 3000 BC to 2500 BC. Pottery found here is of the grooved ware style which was found at the Standing Stones of Stenness, close to the exceptional Maeshowe passage grave type chambered cairn of about the same period. The nearby Ring of Brodgar circle of standing stones was one of the first to be analysed by Professor Alexander Thom to establish the likely use of standing stones as astronomical observatories. Another Neolithic village has been found in the vicinity at Barnhouse Settlement. The brochs of Orkney occur on several islands. Many of these structures, such as Burroughston Broch on Shapinsay, are isolated fortified houses. Others, such as the Broch of Gurness, are surrounded by numerous other dwellings and ancillary structures. In many cases the brochs also are surrounded by elaborate ditch and rampart defences. Both Burroughston Broch and the Broch of Gurness have interesting guard chambers within their thick drystone walls to monitor the single entrance passages. Iron Age The Iron Age brought impressive "Brochs" or round towers, and "weems" or underground houses. Such implements as have survived are primitive, and include quern-stones (for grinding grain), stone whorls and bone combs used in primitive forms of weaving, and specimens of simple pottery ware. Little is known of the