Pointers: Consider calling ahead (allow three weeks and call during weekday business hours) for a free 90-minute highlights tour (202/673-4954). Not recommended for kids under 4. The tour guide will tell you how to look at the animals; where, why, and when to look; and fill your visit with lots of surprises. Enter the zoo at the Connecticut Avenue entrance; you will be right by the Education Building, where you can pick up a map and find out about feeding times and any special activities. Note that from this main entrance, you're headed downhill; the return uphill walk can prove trying if you have young children and/or it's a hot day. As noted below, the zoo does rent strollers and offers plenty of refreshment stands.

The zoo animals live in large, open enclosures--simulations of their natural habitats--along two easy-to-follow numbered paths, Olmsted Walk and the Valley Trail. You can't get lost, and you won't unintentionally miss anything.

You can hang out for an hour in Amazonia peering up into the trees and you still won't spy the sloth--do yourself a favor and ask the attendant where it is.

Zoo facilities include stroller-rental stations; a number of gift shops; a bookstore; and several paid-parking lots. The lots fill up quickly, especially on weekends, so arrive early or take the Metro. Snack bars and ice-cream kiosks are scattered throughout the park.