Economy of Devon (chewing gum) and HMNB Devonport (the largest naval base in western Europe) are in Plymouth. Torquay was home to Beverage Brands, the producers of WKD Original Vodka. Britannia Royal Naval College is at Dartmouth. Mining for tin and copper was carried on in Devon from ancient times until the 1930s: see Dartmoor tin-mining. Agriculture has been an important industry in South West England since the 19th century: approximately 80% of land in the South West of England is in agricultural use (19.6% of England's total). In the later 19th and early 20th centuries there were a number of potteries in
Royal Naval College, Greenwich Christopher Wren and built between 1696 and 1712, then intended to serve as the Greenwich Hospital, a home for disabled sailors. This closed in 1869, when the pensioners were transferred to other places, leaving the buildings available for a new use. The site of the former hospital had once been occupied by the medieval Palace of Placentia, or "Palace at Greenwich", begun by Humphrey, Duke of Gloucester, in 1428. After the Royal Navy departed in 1998 the buildings were opened to the public as the Old Royal Naval College. The President of the College was a full-time post until 1982