The free zoo – which opened in 1868 – is one of Chicago’s most popular attractions, filled with families strolling by gorillas, lions, zebras, and other exotic creatures. Top exhibits include the Regenstein African Journey, which puts you close to pygmy hippos, dwarf crocodiles, and hissing cockroaches. The Ape House pleases with its swingin’ gorillas and chimps. And Farm-in-the-Zoo offers...

Beluga whales, frolicking dolphins, and sharks are the top draws at the Shedd. The first two groups swim in the Oceanarium, which mimics the habitat off the Pacific Northwest coast. For sharks, head to the Wild Reef exhibit, where two dozen ferocious, finned fish cut through the waters as in a Philippines reef ecosystem. The penguins toddling around the Polar...