Ray Meibaum / Saint Louis Zoo

No. 3 Saint Louis Zoo, MO

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Annual Visitors: 2,934,753

The Saint Louis Zoo has the country’s most active AZA Species Survival Plans, which are long-term programs that help endangered species thrive—here, notably, a family of Asian elephants, Amur tigers, horned guans, and Chinese alligators. But that’s not to say more common animals can’t share the spotlight. Eleven lucky sea lions now live in $18 million digs at the new Sea Lion Sound. Visitors can watch the graceful mammals bask on rock ledges or swim overhead from a clear, 35-foot underwater tunnel, the first in North America.

Free admission; stlzoo.org.

America's Most-Visited Zoos

No. 3 Saint Louis Zoo, MO

Annual Visitors: 2,934,753

The Saint Louis Zoo has the country’s most active AZA Species Survival Plans, which are long-term programs that help endangered species thrive—here, notably, a family of Asian elephants, Amur tigers, horned guans, and Chinese alligators. But that’s not to say more common animals can’t share the spotlight. Eleven lucky sea lions now live in $18 million digs at the new Sea Lion Sound. Visitors can watch the graceful mammals bask on rock ledges or swim overhead from a clear, 35-foot underwater tunnel, the first in North America.

Free admission; stlzoo.org.

Ray Meibaum / Saint Louis Zoo

America's Most-Visited Zoos

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