A walk yesterday to Long Bridge Park, which is a bit of a misnomer since there’s not really a bridge and barely a park. But who’s counting when it’s 70 degrees on February 7?

What Long Bridge is, though, is window on the perpetual motion of a busy American city.

The walk adjoins the train tracks, and yesterday, in just 10 minutes, I saw a freight train, Amtrak and the Virginia Railway Express commuter express all chugging along.

East of the train tracks is the George Washington Parkway, where I would later spend close to an hour inching my way home. But at 1 p.m. the traffic is moving, and the cars are like flies skimming the surface of a pond where stately swans (the trains) hold the eye.

Finally, there are the planes taking off and landing at National Airport, just across the way. The low jets fill the sky as they roar heavenward.

It’s an invigorating stroll. I’m moving, the trains, planes and cars are moving. I try to catch all three in my gaze at the same time, to savor their motion and amplify my own.