Does the Washington Metro offer day passes for tourists?

Yes. You can purchase a one day fare card online or at the fare card vending machines in any station for $9. It is valid anytime on Sat, Sun, and Holidays, and after 9:30 AM on Mon thru Fri. This info is on their website: a href="http://www.wmata.com/fares/purchase/passes.cfm" rel="nofollow"http://www.wmata.com/fares/purchase/pass…/a