Puget Sound (pyōˈjĕt) [key], arm of the Pacific Ocean, NW Wash., connected with the Pacific by Juan de Fuca Strait, entered through the Admiralty Inlet and extending in two arms c.100 mi (160 km) S to Olympia. The sound, which receives many streams from the Cascade Range, has numerous islands and is navigable for large ships. Along its shores are important ports and commercial cities; the Puget Sound Naval Shipyard is at Bremerton. The Puget Sound lowland, which extends south from the sound, is the most densely populated area of Washington; Seattle and Tacoma are the principal cities. The sound was discovered in 1792 by English Capt. George Vancouver and named for his aide, Peter Puget, who explored it.