The west coast of the United States, at the intersection of North America and the Pacific Ocean, runs northwest from the Mexican border that divides California from Baja California and San Diego from Tijuana to Point Conception and Point Arguello, then in a north-northwesterly direction past Monterey Bay and San Francisco Bay and the Golden Gate until it reaches the bulge of Cape Mendocino. It then follows a mostly straight northerly course along Oregon and Washington, punctuated by Cape Blanco, the output of the Columbia River, and the openings into Willapa Bay and Grays Harbor, until it reaches Cape Flattery at the northwestern tip of the Olympic Peninsula. It then takes a dramatic turn eastward, along the northern end of the Olympic Peninsula along the Strait of Juan de Fuca, and then includes the land surrounding the many inlets and bays of northwestern Washington State (the most famous of which being Puget Sound), and the land along the southeastern edge of the Strait of Georgia. It then takes a huge leap past Canada (which we'll ignore, because that's what we Merkins like to do) to the Alexander Archipelago along the panhandle of Alaska, from where it arcs to the northwest and then down to the southwest along the Gulf of Alaska and out to the end of the Aleutian Islands. If you're feeling especially ambitious, you could call Hawaii part of the "West Coast", but that would be rather silly.
The west coast of the United States is positioned along the northeastern Pacific Rim, and the seismically active Ring of Fire. The coast is punctuated by such famous faults as the San Andreas Fault and the lesser known but potentially more dangerous Cascadia Subduction Zone. The faults along the coast have produced such famous earthquakes as the great San Francisco quake of 1906, the 1989 Loma Prieta Earthquake, the 1994 Northridge Earthquake, most recently the 2001 Nisqually Earthquake, and of course the 1964 Prince William Sound Earthquake in Alaska, which at 9.2 magnitude was the second largest quake ever recorded. Another notable feature of the Ring of Fire is the series of volcanos found generally around 150km inland, which include the famous Mount St. Helens, which erupted violently in 1980, and now sports a blown-off top. Other well-known volcanos in this chain include Mount Rainier, and Mount Hood, and numerous lesser-known volcanos line the coast, such as Three Sisters in central Oregon and Mount Spurr in Alaska, which erupted three times in the summer of 1992, releasing a great eruption (ash) cloud that dumped on and annoyed the citizens of Anchorage.
The west coast of the United States is an emerging coast, as opposed to the submerging east coast. The west coast is thus considerably more rugged, and features fewer sloping coastal plains and no barrier islands. The topography of the west coast (excluding Alaska) is generally consistent. There is in many places a narrow coastal plain, which ends in the Coast Range, a generally low range of mountains with passes as low as about 600 meters and peaks as high as about 2000 meters, with very few mountains extending beyond the timberline, with the exception of the Olympic Mountains, which reach their peak of 2428 meters at Mount Olympus. These mountains tend to be extremely rainy, with annual rainfalls exceeding 600cm (240in.) in parts of the Olympic Mountains. On the east side of the Coast Range are found fertile valleys, such as the Central Valley in California and the Willamette Valley in Oregon. These valleys end in the east as they ascend into the great Cascade Range in Washington and Oregon] and the Sierra Nevada in California, with the highest peaks being Mount Rainier in Washington (4392m), Mount Hood in Oregon (3426m), and Mount Whitney in California (4418m). To the east of these mountains lies a great rain shadow and desert, with such interesting features as the Channeled Scablands in eastern Washington, eastern Oregon's high desert plateau, and Death Valley and the Mojave Desert in California. Most lands to the west of this rain shadow are relatively moist, as with all west coasts in temperate latitudes, with the exception of southern parts of California.
Major cities on or very near the west coast of the U.S. include San Diego, Los Angeles, San Francisco and the Bay Area, Portland, and Seattle, Tacoma, and the Puget Sound area. Major drainages along the west coast include the Columbia River, the Klamath River, and the San Francisco Bay, fed by the Sacramento and San Joaquin rivers.
Due to the prevailing westerly winds in the temperate zones, most west coasts are rather moist, and very few deserts are located immediately along a west coast. Notable exceptions to this include the Namib Desert in southwestern Africa in Namibia, and the Atacama Desert in South America in northern Chile. The Atacama Desert, trapped between the huge Andes mountains and the cold Humboldt Current in that part of the Pacific Ocean, is in fact the driest desert in the world, with some areas that have never had rain recorded.