Greenwich , outer borough (1991 pop. 200,800) of Greater London, SE England, on the Thames River. Manufactures include telephone equipment and underwater cable. The system of geographic longitude and time-keeping worked out at the famous Royal Observatory there have become standard in most countries of the world; the prime meridian, or long. 0°, passes through the observatory. The functions of the observatory were transferred to Herstmonceux, Sussex in 1946, and later to Cambridge (1990). Greenwich has nearly 9 mi (14.5 km) of river frontage; the huge Millennium Dome, constructed to celebrate the year 2000, is on the waterfront. Nearby Woolwich's docks and shipbuilding facilities were important from the 16th to the mid-19th cent. The Royal Naval College is in the borough. The college building, partially designed by Christopher Wren , was originally a home for disabled sailors. On the site of the present structure (begun in the late 17th cent.) stood a palace that was the birthplace of Henry VIII, Mary I, and Elizabeth I; Edward VI died there. Greenwich's National Maritime Museum is partly housed in a building designed by Inigo Jones for Anne of Denmark. The Royal Military Academy was at Woolwich until 1947, when it merged with the Royal Military College at Sandhurst. Both Greenwich and Woolwich are mentioned in documents dating from the 10th cent. and appear in the Domesday Book .