Monterey Bay Aquarium, Monterey

This is one of the best designed aquariums going. A unique feature is the two-story tank, home to a kelp forest in which swim sunfish, sharks, and the occasional diver tasked with squeegeeing the algae off the tank walls. Sand dabs are displayed in shelf-like tanks ideally suited to the flat fish, and a school of sardines swim in an endless circle in their cylindrical tank home. If you want to interact with some aquatic dwellers, you're invited to pet the bat rays (oddly velvet-like). The jellyfish display shows that they are like something from another planet.