The world's largest assortment of finned, gilled, amphibious, and other aquatic creatures swims within the marble-clad confines of the John G. Shedd Aquarium. Though it could simply rest on its superlative exhibits - like beluga whales in a 4 million gallon (15 million liter) aquarium - the Shedd makes a point of trying to tie concepts of ecosystems, food webs, and marine biology into its presentation of super cool animals.
Permanent exhibits include the multilevel Oceanarium, which mimics ocean conditions off the northwest coast of North America. The beluga whales inside are remarkably cute creatures that come from the pint-size end of the whale scale. Their humped heads and natural “smiles” make them look eerily human. You'll also see Pacific white-sided dolphins, harbor seals, and sea otters.
Don't linger only on the main floor; you can go underneath the cement seats and watch the mammals from below through viewing windows. The “Wild Reef” exhibit will have sharkophiles and sharkophobes equally entranced; over a dozen sharks cut through the waters in a simulation of a Philippines reef ecosystem. And the “Amazon Rising” exhibits offer a captivating look at a year in the Amazon River and rain forest.
The John G. Shedd Aquarium is located on the Museum Campus in the South Loop, just off Lakeshore Drive. Both buses and El lines get you here. Nearby attractions include the Adler Planetarium and Astronomy Museum and the Field Museum of Natural History, which are all within walking distance.
Some of the newer and special exhibits sell out early in the morning; consider buying tickets on the website beforehand to ensure entry. The whole place can be easily covered in two to three hours.