California is located in a hot zone of fault lines, the most notorious of them the San Andreas Fault.

Narrator: While experts can't know exactly when a quake will occur, they have a pretty good idea of where. But when it hits, what will that actually look like? Here's what experts say could happen in the seconds, hours, and days after the big one. But neither of these compare to the long-awaited big one, which scientists predict will eventually rattle the golden coast. Narrator: On July 4, 2019, Ridgecrest, California, was hit with a 6.4 magnitude earthquake and then a 7.1 just one day later. Here's what will happen if the big one hits the West Coast. Narrator: Catastrophic earthquake scenarios have played out on the silver screen for decades, terrifying viewers with quakes that can collapse skyscrapers or topple entire cities. Here's what experts say could happen in seconds, hours, and days after the Big One hits the West Coast.Parts of the San Andreas fault have not ruptured in over 200 years, meaning it's overdue for a high-magnitude earthquake commonly referred to as 'The Big One.'.California is located in a hot-zone of fault lines that can rupture without warning.