The Dulles airport is the most beautiful airport building I've seen, both as a public sculpture and as an interior space. The roof of the atrium is an asymmetrical catenary curve (I think), extruded in concrete. Each slab is a complete catenary in profile.

Operationally, the airport has some limitations. Fourteen metal detectors serve the entire flow of passengers through Dulles. Around 4:00, all comers wait in the same long line, which winds through three non-velvet ropes, then down the length of the atrium, around the check-in desks, and back down to the other end of the atrium, where it makes a fuzzy 180 (outside the ropes by now) and back down to the opposite end of the hall. I waited in line an hour before beginning to empty my pockets.

For whatever reason (conomial relationship with an unknown terrorist-connected individual?), I was selected for screening at both ends of this journey. With my usual Zen calm, I submitted graciously both times.

The second time, they found something in my bag that most of us now realize is not permitted on an airplane: a swiss army knife. I'd thrown it in my bag when I went for hike two weeks ago, and promptly forgot about it. At least I recognized it when I saw it: the classic Swiss Army logo as well as the multiple retractable knives and saws are some the indicators that tipped me off. The metal-detector operators in San Francisco and Dulles didn't manage to see anything wrong with this, and neither did the person who searched my bag by hand in San Francisco.

Fly safe, y'all.