WASHINGTON — The snow crunched underfoot as volunteers carrying flashlights shimmied their way through a small opening in a chain link fence separating Crystal City from the Virginia Railway Express tracks.

One by one, they negotiated an icy incline and crossed the tracks onto a makeshift trail leading to a homeless encampment.

A snowy mattress marked the entrance. Tattered sweatshirts hung frozen on a clothesline, and leftover trash hinted at what used to be there.

“Hello!” calls David Ordo