And it was at Noltland on Westray too, that one of the most impressive castles in Orkney, and indeed the Northern Isles, was built, Noltland Castle. The castle was commissioned in the 1560s by Gilbert Balfour, who probably played the leading role in the murder of Lord Darnley, consort of Mary, Queen of Scots. Balfour married Margaret Bothwell, the sister of Adam Bothwell, Bishop of Orkney who endowed him with Westray, when it was episcopal property. The Castle is situated above the Bay of Pierowall, was built in the 1560s. It is notable for an unusually large spiral staircase, "second only to Fyvie Castle, while its triple tiers of gunloops are without parallel in Scotland, if not Europe". However, Balfour was executed by the Swedes before he could use it.