Yesterday I walked on the Washington and Old Dominion trail, a long ribbon of asphalt that runs from the inner suburbs to the foothills of the Blue Ridge. It was a fine spring afternoon, trees bursting pink and white, birds flitting from branch to post.

Bikers zoomed by. “Passing on the left.” So many of them that I moved to the narrow gravel shoulder. “Share the trail,” the signs said. This felt less like sharing and more like abandoning. I walked quickly — and not just for exercise. It was scary out there.

Two weeks ago I moseyed along the same stretch of path. It was still winter and I had the trail to myself. Yesterday I longed to be back in that gray afternoon, warming myself up on an empty trail.