At 5:12 am on April 18 , 1906 , a major earthquake struck San Francisco and northern California . As buildings collapsed from the shaking , ruptured gas lines ignited fires that spread across the city and burned out of control for several days . With water mains out of service , the Presidio Artillery Corps attempted to contain the inferno by dynamiting blocks of buildings to create firebreaks . More than three-quarters of the city lay in ruins , including almost all of the downtown core . Contemporary accounts reported that 498 people lost their lives , though modern estimates put the number in the several thousands . More than half of the city 's population of 400,000 was left homeless . Refugees settled temporarily in makeshift tent villages in Golden Gate Park , the Presidio , on the beaches , and elsewhere . Many fled permanently to the East Bay
earthquake struck San Francisco
1906 San Francisco earthquake
San Francisco