It's an armada of motorcycles, thousands of them, the mufflers removed from every one, it seems, so a low steady cyclical growl floats over the whole city -- and from the horizon, for the bikers are across the river as well, in the neighborhood close to Arlington National Cemetery, which is the magnet pulling all this metal to Washington, D.C. each year during Memorial Day weekend. It's called Rolling Thunder (which was also, not so coincidentally, the name of a bombing campaign during the Vietnam war).
The usual tourists wander around, of course, taking the usual pictures of the usual monuments. But more awe-inspiring is the temporary installation of artwork on the streets downtown. There are long rows of parked motorbikes, customized to the point of mutation, parked at angles that seem like a temptation to gravity and the domino effect. The place is full of sweaty, beer-swilling, heavily tattooed bikers. And you should see their husbands.