Plymouth Sound

Plymouth Sound, or locally just The Sound, is a bay on the English Channel at Plymouth in England.

Its southwest and southeast corners are Penlee Point in Cornwall and Wembury Point in Devon, a distance of about 3 nautical miles (6 km). Its northern limit is Plymouth Hoe giving a north-south distance of nearly 3 nautical miles (6 km).

The Sound has three water entrances. The marine entrance is from the English Channel to the south, with a deep-water channel to the west of the Plymouth Breakwater. There are two freshwater inlets: one, from the northwest, is from the River Tamar via the Hamoaze and Devonport Dockyard, the largest naval dockyard in western Europe. The other, at northeast, is from the River Plym disgorging into its narrow estuary, Cattewater harbour between Mount Batten and the Royal Citadel.

In addition to ships of the Royal Navy, large commercial vessels, including ferries to France and Spain use the Sound from Millbay Docks. Fishing vessels use it from Sutton Harbour beside the old town of Plymouth, called the Barbican. There are marinas at Sutton Harbour, Mount Wise in the Hamoaze and at Turnchapel. Waterborne traffic in the Sound is controlled by the Queen's Harbour Master for Plymouth.

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