Seattle Geography

Seattle is located between an inlet of the Pacific Ocean to the west called Puget Sound and Lake Washington to the east. The city's chief harbor, Elliott Bay, is an inlet of the Sound. West beyond the Sound are the Kitsap Peninsula and Olympic Mountains, on the Olympic Peninsula; east beyond Lake Washington and the eastside suburbs are Lake Sammamish and the Cascade Range. Lake Washington's waters flow out through the Lake Washington Ship canal, a series of two man-made canals and Lake Union, to the Hiram C. Chittenden Locks at Salmon Bay, to Shilshole Bay, which is part of Puget Sound. The sea, rivers, forests, lakes, and fields were once rich enough to support one of the world's few sedentary hunter-gatherer societies. Opportunities for sailing, skiing, bicycling, camping, and hiking are nearby and accessible almost year-round.

The city itself is hilly, though not uniformly so. Like Rome, the city is said to lie on seven hills; the lists vary, but typically include Capitol Hill, First Hill, West Seattle, Beacon Hill, Queen Anne, Magnolia, and the former Denny Hill. The Wallingford and Mount Baker neighbourhoods are technically located on hills as well. Many of the hilliest areas are near the city center, with Capitol Hill, First Hill, and Beacon Hill collectively constituting something of a ridge along an isthmus between Elliott Bay and Lake Washington. The break in the ridge between First Hill and Beacon Hill is man-made, the result of two of the many regrading projects that reshaped the topography of the city center. The topography of the city center was also changed by the construction of a seawall and the artificial Harbor Island (completed 1909) at the mouth of the city's industrial Duwamish Waterway.

The man-made Lake Washington Ship Canal incorporates four natural bodies of water: Lake Union, Salmon Bay, Portage Bay, and Union Bay, connecting Puget Sound to Lake Washington.

Seattle is in an earthquake zone and has experienced a number of significant quakes, most recently (as of 2007) the magnitude 6.8 Nisqually Earthquake, February 28, 2001, which did significant architectural damage, especially in the Pioneer Square area (built on reclaimed land, as are the Industrial District and part of the city center), but caused no fatalities. Other strong quakes occurred on December 14, 1872 (estimated at 7.3 or 7.4 magnitude), April 13, 1949 (7.1), and April 29, 1965 (6.5). The 1949 quake caused eight known deaths, all in Seattle; the 1965 quake caused three deaths in Seattle directly, and one more by heart failure. Although the Seattle Fault passes just south of the city center, neither it nor the Cascadia subduction zone has caused an earthquake since the city's founding. The Cascadia subduction zone poses the threat of an earthquake of magnitude 9.0 or greater, capable of seriously damaging the city and collapsing many buildings, especially in zones built on fill.

According to the United States Census Bureau, the city has a total area of 369.2 km˛ (142.5 mi˛), 217.2 km˛ (83.9 mi˛) of which is land and 152.0 km˛ (58.7 mi˛) water. The total area is 41.16% water.