Exactly one year ago Thursday, a 5.8 magnitude earthquake centered in Mineral, Virginia, rocked the Eastern seaboard, causing tremors from Georgia all the way to New England.

Where were you when it happened?

The quake was centered three-to-four miles beneath the Virginia town, and it was likely felt by more people in the country than any other earthquake in US history. It’s believed that one-third of America’s population felt the earth tremble that day.

Although there were no serious injuries, the quake caused more than $200 million in damages, including cracks in the Washington Monument, which remains closed to this day. Officials expect that the landmark will reopen sometime in 2014 after repairs costing $15 million.

Since the quake, more than 450 aftershocks have been recorded, and the central Virginia seismic zone is being carefully studied by scientists to determine if more are to come.

In addition, some states have significantly rethought their emergency response plans. Virginia, Maryland and the District of Columbia, for example, are taking steps to educate the public about how to respond to a quake. In other places like New York City, only minor changes have been made to internal emergency planning.

[NBC Washington]