Puget Sound is a sound along the northwestern coast of the U.S. state of Washington, an inlet of the Pacific Ocean, and part of the Salish Sea. It is a complex estuarine system of interconnected marine waterways and basins, with one major and one minor connection to the open Pacific Ocean via the Strait of Juan de Fuca—Admiralty Inlet being the major connection and Deception Pass being the minor. Flow through Deception Pass accounts for about 2% of the total tidal exchange between Puget Sound and the Strait of Juan de Fuca.Puget Sound extends approximately 100 miles (160 km) from Deception Pass in the north to Olympia, Washington in the south. Its average depth is 450 feet (140 m) and its maximum depth, off Point Jefferson between Indianola and Kingston, is 930 feet (280 m). The depth of the main basin, between the southern tip of Whidbey Island and Tacoma, Washington, is approximately 600 feet (180 m).The term “Puget Sound” is used not just for the body of water but also the Puget Sound region centered on the sound.