This zoo has more than just 500 animals and 3,000 plant species. Although the bounty of both plants and animals put the Cincinnati Zoo in the top tier of American zoos, another reason to go is the buildings. The Elephant House, Reptile House and the Passenger Pigeon Memorial elevated the zoo to National Historic Landmark status in 1987. It is also the second-oldest zoo in the country, having opened in 1875. The zoo has “Sarah,” the world’s fastest land mammal. This crowd-pleasing cheetah earned her status by running a 100-meter sprint in 6.13 seconds. At the zoo’s new Cheetah Encounter, part of Phase I of the Africa Savannah expansion (there are three more to go), you can watch Sarah and her three cheetah buddies run. Another of the zoo’s exhibits, Giraffe Ridge, puts visitors at eye level with those guys with incredibly long necks. Check out the schedule of “meet the Zoo Keeper” and animal encounters held throughout the day.