To make the Exploratorium safer in an earthquake, the architects behind our building installed a seismic joint—a space near the front of the building where the part resting on land is separated from the part resting on Pier 15, so that each can move independently. (Don't worry, you won't have to jump across the gap when you visit—we've covered the joint with a moveable floor.) Watch how we cut our concrete building in two for the sake of seismic safety.