of that castle remains; the existing castle probably dates from the 15th century. In 1539 King Henry VIII ordered the construction of Portland Castle for defence against attacks by the French; the castle cost £4,964 (equivalent to £ in ). It is one of the best preserved castles from this period, and is opened to the public by the custodians English Heritage. In the 17th century, chief architect and Surveyor-General to James I, Inigo Jones, surveyed the area and introduced the local Portland stone to London, using it in his Banqueting House, Whitehall, and for repairs on St Paul's Cathedral. His successor, Sir Christopher Wren, an architect and the Member of Parliament for nearby Weymouth, used six million tons of white Portland limestone to rebuild destroyed parts of the capital after the Great Fire of London of 1666. Well-known buildings in the capital, including St Paul's Cathedral and the eastern front of Buckingham Palace feature the stone. After the First World War, a quarry was opened by The Crown Estate to provide stone for the Cenotaph in Whitehall and half a million gravestones for war cemeteries, and after the Second World War hundreds of thousands of gravestones were hewn for soldiers who had fallen on the Western Front. Portland cement has nothing to do with Portland; it was so named due to its similar colour to Portland stone when mixed with lime and sand. There have been railways in Portland since the early 19th century. The Merchant's Railway was the earliest—it opened in 1826 (one year after the Stockton and Darlington railway) and ran from the quarries at the north of Tophill to a pier at Castletown, from where the Portland stone was shipped around the country. The Weymouth and Portland Railway was laid in 1865, and ran from a station in Melcombe Regis, across the Fleet and along the low isthmus behind Chesil Beach to a station at Victoria Square in Chiswell. At the end of the 19th century the line was extended to the top of the island as the Easton and Church Ope Railway, running through Castletown and ascending the cliffs at East Weares, to loop back north to a station in Easton. The line closed to passengers in 1952, and the final goods train (and two passenger 'specials') ran in April 1965. The Royal National Institution for the Preservation of Life from Shipwreck stationed a lifeboat