Great Shake Out: Millions of Californians participate in annual earthquake drill

OAKLAND, Calif. (KGO) -- Millions of people across California participated in an annual earthquake drill on Thursday morning.

The Great California Shakeout happens every year on the third Thursday of October and is meant to make sure we're all ready for when "the big one" hits.

Less than an hour before the Shake Out drill, a 3.1 earthquake struck in Berkeley, serving as a reminder to always be prepared.

MORE: Preliminary 3.1 earthquake hits Berkeley, USGS says, hours before quake drill

Experts say to remember these three simple steps: drop, cover and hold on.

Anyone with the "MyShake" earthquake early warning app received an alert at 10:16 a.m. for the drill. At the same time, BART trains automatically slowed down to 27 miles per hour before coming to a brief stop.

On Thursday, ABC7 News reporter Zach Fuentes also got to experience what a 7.0 earthquake felt like in a simulator, where he was thrown to the ground along with books flying off shelves.

MORE: Seismologist warns stress continues to build on Hayward Fault but probability of 'big one' is low

Preparing for a serious earthquake extends beyond the drill.

We should all have a kit with critical supplies to keep our families safe in the immediate hours and days after a disaster strikes.

The quake comes just a day before the 36th anniversary of the 1989 Loma Prieta Earthquake. Oakland Mayor Barbara Lee was here in the aftermath of the devastating quake and says the city is in a much stronger place to respond.

"We're building resilience hubs to support our neighborhoods in times of crisis," Mayor Lee said. "We did not have those in 1989. We're making infrastructure improvements through our seismic strengthening program, we did not have that in 1989 we've enhanced our emergency alert system."

Find more information on what to put in your kit, or what to do in case of a major earthquake here.