It has been quite a while since I last flew in to National Airport in Washington DC (or Virginia if you are being accurate). My recent visit to DC took me through the airport but not through the main terminal that I have used in the last decade. Southwest operate from the original terminal which, I have to admit, I didn’t realize was still in use.
This is quite a distance from the rest of the airport and so you have a ten minute walk to get to the access to the metro station. It takes you all the way through the original terminal building which is a pretty impressive art deco structure. I did not have a camera other than that on my phone but I did grab a few quick pictures of this building which seems to have been restored as it is in good condition. It seems to be a bit of a gem that is missed by most people traveling through the airport.