Plymouth, city and unitary authority (1991 pop. 238,583), SW England, on Plymouth Sound. The three towns that Plymouth has comprised since 1914 are Plymouth, Stonehouse, and Devonport; the suburbs of Plympton and Plymstock were added to the city in 1967. Modern Plymouth is well situated, mostly on a peninsula between the estuaries of the Plym and Tamar rivers. The southern waterfront and adjacent promenade are called the Hoe. The city is an important port and naval base. Foodstuffs and raw materials are imported, and manufactures such as machine tools, precision instruments, and chemicals are exported. Other items traded are granite, marble, kaolin, and fish. In Stonehouse is a Royal Naval Hospital (1762). The Royal Marine Barracks and Naval Dockyard (1691) are in Devonport.
In 1588 the port was the rendezvous of the anti-Armada fleet. From there Sir Francis Drake, Sir Richard Hawkins, Sir Walter Raleigh, and several later explorers set forth. It was the last port touched by the Mayflower before its American voyage. Plymouth was held by the parliamentarians for four years during the civil war, when the rest of Devon and Cornwall were royalist. The first English factory to make Chinese porcelain was established in Plymouth in 1768. A tablet commemorates the arrival in 1919 of the first transatlantic airplane.
Among the principal points of interest on the Hoe are the old Royal Citadel (17th cent.), the upper part of Smeaton's lighthouse brought from Eddystone, an Armada memorial, and a naval war memorial. Also noteworthy are the marine-biological laboratories, the aquarium, the City Museum and Art Gallery, the Gothic guildhall, several 15th-, 16th-, and 17th-century churches, and the Roman Catholic cathedral. The Royal Naval Engineering College is in Devonport, and technical and teacher-training schools are located in Plymouth.