An earthquake can be an abstract concept, especially when you don't know if it will strike now or decades from now.

But an earthquake simulator operated by northern California-based Ready America can in five seconds make earthquakes a lot more relevant.

The simulator is built into a large cargo trailer, and special hydraulics shake it violently for between five and 10 seconds, giving you the feel for a small portion of a magnitude 8.0 earthquake, says operator Trevyn Reece.

Ready American sells earthquake preparedness kits and supplies.

The big shaker operated between 11 a.m. and 3 p.m in Occidental Park in Seattle's Pioneer Square neighborhood Thursday. Last year it was set up in Westlake Park and was brought in as part of an awareness event by the Seattle Office of Emergency Management.

So what's it like? We'll take you on board.