Answer the following question: Information: - Balfour Castle is a historic building on the southwest of Shapinsay , Orkney Islands . Though built around an older structure that dates at least from the 18th century , the present castle was built in 1847 , commissioned by Colonel David Balfour , and designed by Edinburgh architect David Bryce . - Kirkwall is the largest town and capital of the Orkney Islands of Scotland. The town is first mentioned in "Orkneyinga saga" in the year 1046 when it is recorded as the residence of Rognvald Brusason the Earl of Orkney, who was killed by his uncle Thorfinn the Mighty. In 1486, King James III of Scotland elevated Kirkwall to the status of a royal burgh; modern roadsigns still indicate "The City and Royal Burgh of Kirkwall". - Shapinsay is one of the Orkney Islands off the north coast of mainland Scotland. There is one village on the island, Balfour, from which roll-on/roll-off car ferries sail to Kirkwall on the Orkney Mainland. Balfour Castle, built in the Scottish Baronial style, is one of the island's most prominent features, a reminder of the Balfour family's domination of Shapinsay during the 18th and 19th centuries; the Balfours transformed life on the island by introducing new agricultural techniques. Other landmarks include a standing stone, an Iron Age broch, a souterrain and a salt-water shower. - A broch is an Iron Age drystone hollow-walled structure of a type found only in Scotland. Brochs belong to the classification "complex atlantic roundhouse" devised by Scottish archaeologists in the 1980s. Their origin is a matter of some controversy. The theory that they were defensive military structures (an Iron Age equivalent to the castles and tower houses of medieval Scotland) is not accepted by many modern archaeologists (see the 'general references' below), while the alternative notion that they were farmhouses is dismissed by some others. Although most stand alone in the landscape, some examples exist of brochs surrounded by clusters of smaller dwellings. - The Iron Age is an archaeological era, referring to a period of time in the prehistory and protohistory of the Old World (Afro-Eurasia) when the dominant toolmaking material was iron. It is commonly preceded by the Bronze Age in Europe and Asia with exceptions and the Stone Age in Africa. Meteoric iron has been used by humans since at least 3200 BC, but ancient iron production did not become widespread until the ability to smelt iron ore, remove impurities and regulate the amount of carbon in the alloy were developed. The start of the Iron Age proper is considered by many to fall between around 1200 BC to 600 BC, depending on the region. In most parts of the world, its end is defined by the widespread adoption of writing, and therefore marks the transition from prehistory to history. - Souterrain (from French "sous terrain", meaning "under ground") is a name given by archaeologists to a type of underground structure associated mainly with the European Atlantic Iron Age. Given the information above, choose from the list below the object entity that exhibits the relation 'located in the administrative territorial entity' with the subject 'balfour castle'. Choices: - africa - edinburgh - europe - king - kirkwall - mainland - most - of - orkney - orkney islands - scotland
Answer:
scotland