Just down the road from the Cathedral, the National Zoo is yet another free play zone brought to you by the Smithsonian. Meander by the Giant Pandas, keep an eye out for the orangutans, which can travel freely on a system of cables 40 feet above your head, and if you have small children with you, make your way all the way down to the petting farm and the pizza-garden playground.

• 1. National Zoo
  3001 Connecticut Avenue NW, Washington, DC 20008; 202-633-4800 38.929765-77.055131 nationalzoo.si.edu