At 5:12 in the morning of April 18, 1906, a major earthquake hit San Francisco and the northern California coast in what is still today counted among the top three worst natural disasters in United States history, along with the Galveston Hurricane (1900) and Hurricane Katrina (2005). More than 3,000 people died in the quake and fires that erupted from broken gas mains and burned out of control in the damaged city, and more than 80% of San Francisco was destroyed. the death toll remains the largest death toll in the history of California. Refugee camps remained operating nearly three years later as ore than a quarter million people -- more than 60% of the total population -- were rendered homeless. It likely registered 7.9 with the epicenter two miles offshore, and it was felt from Los Angeles to Oregon on the coast and inland into Nevada.
 
 
Recommended Resources
About.com: 1906 San Francisco Earthquake
Presents details about the Great Quake, its historical importance, and links to photographs, sites, and articles about the event, including an article written by Jack London about the aftermath.
http://history1900s.about.com/cs/sfearthquake/p/sfquake.htm
Bancroft Library: 1906 San Francisco Earthquake and Fire
Berkley's Bancroft Library displays this online exhibit centering on the Great Quake of 1906, with photographs and interactive maps as well as 360-degree panoramic display of San Francisco as it stood after the damage.
http://bancroft.berkeley.edu/collections/earthquakeandfire/index2.html
San Francisco Earthquake, 1906
With material from the National Archives, this section is a repository of information and photographs of the devastating earthquake and what happened after it was done and the fires extinguished.
http://www.archives.gov/legislative/features/sf/
The 1906 San Francisco Earthquake and Fire
Presents an exhibit which focuses on the earthquake and fire, and goes on to delve into the aftermath and, finally, the rebirth of the city. It displays documents and photographs which are primary sources used by historians and other researchers use for their research. Also contains eyewitness testimony of the damage, the fires, and the struggle to rebuild.
http://www.archives.gov/exhibits/sf-earthquake-and-fire/
The Great 1906 San Francisco Earthquake
The U.S. Geological Survey's mini-site sets forth numerous pages about the quake which destroyed most of San Francisco, including various measurements of the size, casualties and damage , and photographs of the city as it burned and the aftermath.
http://earthquake.usgs.gov/regional/nca/1906/18april/index.php