St. Louis Zoo, Saint Louis, Missouri
Home to more than 650 species, this popular Midwest zoo features creatures of all kinds. Travelers can immerse themselves in the ten-acre River’s Edge exhibit, a naturalistic habitat featuring roaming hyenas, hippos, elephants, and more. Feathered friends-galore can be spotted at the Penguin and Puffin Coast, while Bear Bluffs boasts some less cuddly beasts, such as Grizzlies, Andeans and Sloth bears. “This is a great zoo and the fact that it's free is wonderful for families on a budget,” said one TripAdvisor traveler. Admission is free, but some attractions require a small fee.