There are more than 2,400 zoos to visit in the U.S., each one packed with animals from near and far. Most major cities have a zoo or aquarium, making these fascinating venues a great day trip on any vacation. Zoos in the United States have the added benefit of contributing to research and conservation efforts. Many are working toward providing open-air, cageless enclosures for their animals, resulting in happier creatures in a natural environment. For frequent zoo-goers, memberships help support the care and maintenance of animals and their habitats.

01The San Diego Zoo

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The San Diego Zoo is the largest zoo in the United States, housing over 3,700 animals encompassing more than 650 species. This zoo is unique in that it led the charge of open-air, cageless enclosures for animals and is one of the only zoos in the world to successfully breed the giant panda. The newest exhibit, added in 2017, is called Africa Rocks and cost over $60 million to construct.

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02The Indianapolis Zoo

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The Indianapolis Zoo wins the award for most creative activities! Not only can you view over 1,400 animals and 31,000 plants, but you can swim with dolphins, attend zoo camp, and obtain a personalized animal portrait from a zoos artist. Make sure you don't miss the new long-tailed macaques who love swimming in the water in the hot summer months.

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03The Bronx Zoo

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It's hard to imagine a flourishing zoo filled with lush plants and vivacious animals in the middle of a metropolis like New York City, but the Bronx Zoo offers one of the neatest zoo experiences in the country. The Bronx Zoo is notable for its amazing attention to detail in creating natural habitats that make the animals happy year-round. Add a little adventure to your trip to the zoo: sail on a zipline at the new aerial adventure park.

04The Alaska Zoo

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Alaska has some of the most unique wildlife in the U.S., so it is no surprise that it has an impressive zoo to match. Because of the cold climate, the Alaska Zoo can house animals the southern states can't accommodate. At the Alaska Zoo, you will find snow leopards, Canadian lynx, and reindeer. One of the most beloved elements of this zoo is its efforts to rescue and care for injured and abandoned polar bear cubs.

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05Woodland Park Zoo

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Woodland Park Zoo in Seattle, Washington is a zoological garden that works hard to recreate the natural habitats of its more than 1,000 animals. The Association of Zoos and Aquariums has honored Woodland Park Zoo with multiple awards for Best National Exhibit. Visitors enjoy watching Aibeck grow up. This snow leopard cub was born at the zoo in the summer of 2017.

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06St. Louis Zoo

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The Saint Louis Zoological Park is recognized as a leading zoo in animal management, research, conservation, and education. Thanks to a public subsidy from a cultural tax district, entrance to the zoo is completely free. The biggest attraction at the St. Louis zoo is Kali, an 850-pound polar bear who lives in a brand new $16 million enclosure. The Africa exhibit is also a can't-miss spot.

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07The Houston Zoo

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The Houston Zoo is the second most visited zoo in the United States, with over 2.5 million visitors every year. Even if you can't make it to Texas, you can check in with the animals via the zoo's Rhino, Elephant Yard, and Leafcutter Ant online cams. The zoo is home to one of the largest collections of birds in the United States and you can even spend the night at a zoo sleepover.

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08The Columbus Zoo

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Famous animal researcher and late-night TV guest Jack Hanna is the director emeritus of the Columbus Zoo. Hanna's efforts and promotion have made this one of the top zoos in the United States. A unique aspect of the zoo is its 100,000-gallon coral reef tank teeming with bright tropical fish. Also be sure to check out the Congo exhibit.

09The Cincinnati Zoo

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The Cincinnati Zoo and Botanical Garden is the second oldest zoo in the United States, with a Reptile House dating back to 1875. Although the zoo has been in headlines in recent years for the unfortunate death of its gorilla Harambe, it works hard to save species by breeding animals in a safe and healthy environment. One of guests' favorite activities is getting to know Moe, the adorable two-toed sloth.

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10Henry Doorly Zoo

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The Henry Doorly Zoo and Aquarium is located in Omaha, Nebraska and is known for its glazed geodesic dome. Inside the dome, find an homage to the American Southwest, including dunes, desert, reptiles, and bobcats. Go one level lower to the dark, nocturnal exhibit where you can see naked mole rats and bats.

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