On April 18, 1906, a massive earthquake struck San Francisco, causing widespread destruction and fires that lasted for days. The earthquake, which measured 7.8 on the Richter scale, killed an estimated 3,000 people and left over 250,000 homeless. The destruction included many of the citys buildings, infrastructure, and the waterfront. The event became one of the deadliest and most costly natural disasters in U.S. history. San Franciscos recovery took years, and the earthquake led to significant improvements in building codes and earthquake preparedness.