Leaving DCA to the North on Foot (opens in new tab)

Google Maps thinks it takes half an hour to walk to from DCA to Crystal City, but you can actually do it in fifteen minutes. I really like leaving airports on foot. There's something about it that feels like it shouldn't be possible: between an airplane and your destination there should be some other kind of vehicle, no? It reminds me of the first time I boarded a plane without using a jetway, where walking out on the tarmac just felt wrong. I was in DC the past two days for meetings (my firs...