Visitors tour through the Exploratorium’s cavernous new space at their $300 million home during a pre-opening tour March 25, 2013. The facility in
Visitors tour through the Exploratorium's cavernous new space at their $300 million home during a pre-opening tour March 25, 2013. The facility in Pier 15 along San Francisco's waterfront opens on April 17. (Karl Mondon/Staff)