Yesterday I walked from my office to National Airport. This is not something I thought I would do when I woke up and dressed for work. I wore jeans and sandals for “casual Thursday.” I left my running shoes at home. But I have an old pair of shoes (only one small hole, in the right toe) at the office, so about 3 p.m. I slipped into those, turned off my computer and headed out for the five-mile stroll.

The route to DCA took me down the National Mall, across the 14th Street Bridge and along the Mount Vernon Trail. I was on paths or sidewalks the whole time. I saw tourists, patriots, vendors and cyclists. I heard sirens, jackhammers, street musicians and bike bells.

When I got to Gravelly Point, planes were taking off and landing right overhead, and I could hear a Metro car rattle and a freight train whistle. My walk was part of all the activity around me, was heightened and made whole by it.