When I was a child growing up outside of Philadelphia, one of my favorite places in that city was the Franklin Institute, where, among other things, you could walk inside a giant replica of a human heart. As an adult, I get that same feeling, minus the cheesy recording of a pulse, from the Exploratorium (in the Palace of Fine Arts), San Francisco's legendary science museum in the Presidio. Make sure you experience the tactile dome, a pitch-black maze that you have to navigate by touch (it's worth the $20 premium on top of the $15 admission fee); blow the world's biggest soap bubble, as big around as a beach ball; and dissect a cow's eye.

• 1. Exploratorium
  3601 Lyon Street, San Francisco, CA 94123; 415-397-5673 37.804209-122.448166 exploratorium.edu