April 15, 1981 – Permanent
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National Zoo
3001 Connecticut Ave., NW
Washington, DC

Olmsted Walk

See on Map Floor Plan

The Smithsonian’s National Zoo is home to over a dozen species of primates.

The homestead for the Zoo’s gorillas and orangutans is the Great Ape House. Within the house, floor-to-ceiling viewing panes allow visitors to view these endangered animals up close. Having a choice of how to spend their time is critical to great ape care, so enclosures are designed to provide the animals with opportunities to use their natural behaviors in new and exciting ways. Whether inside or outside, the apes have an opportunity to climb trees and multi-level platforms, rest in a hammock; swing from hanging ropes and fire hoses, engage in enriching activities (such as training and painting) and forage for food.

Walking between the Great Ape House to Think Tank? Look up! Orangutans travel along the O-Line, a 50-foot-high suspended cable track that gives them the freedom to move between their yards at the Great Ape House and Think Tank. Orangutans have the choice to use the O-Line on nice weather days from late morning to the early afternoon.

The interactive Think Tank exhibit is the place to think about animal thinking! Visitors are introduced to orangutans, Allen’s swamp monkeys, Norway rats, and land hermit crabs to explore the concept of thinking through three main themes: language, society and tool use. Learn more about the Zoo’s ongoing primate research projects, see the monkeys illustrate the rules of living in a society, and observe rats navigating their exhibit, highlighting their physical abilities and flexible decision-making skills.

Inside Think Tank, participate in a tug-of-war with an orangutan at the orangutan rope-pull and test their arm strength. Looking at the animals outside? Get caught under a mist of water—turned on by an orangutan—in the Wet Zone. The outdoor orangutan exhibit is fitted with two mister shower heads. The push valves are operable only by the apes, who will have the ability to shower a visitor, themselves or both.

At Gibbon Ridge, visitors can see siamangs swing through the ropes and branches. The Zoo’s tall outdoor enclosures are fitted with platforms, ropes and swings that encourage these lesser apes to navigate their habitat just as they would in the wild. With their long arms and hands, gibbons are adapted to moving fast high in the tree canopy using an arm-over-arm motion called “brachiation.” When walking on the ground, they place their arms above their head for balance.

Ring-tailed lemurs, red-fronted lemurs and black-and-white ruffed lemurs live on Lemur Island. Throughout the day, lemurs may be found basking in the sun, jumping through the trees, or huddled together, often grooming one another to strengthen their social bonds.

Depending on the time of day and weather conditions, all of the lemurs and apes have a choice to be in their indoor or outdoor enclosures. Great apes tend to be active in the morning and nap in the mid to late afternoon. Our gorillas and orangutans also have the option to enjoy some time away from the crowds in off-exhibit areas behind the scenes.