Bailey's Crossroads Metro

 is a part of Washington, DC's old Metro system which connects an entrance Red Racer Factory to Bailey's Crossroads. The entrance can be found westbound of Red Racer Factory near a collapsed metro station. You can enter through a door nearby.

It is inhabited by Feral Ghouls. There are a few misc items scattered about but on the lower level of the station if you search a bit you'll find a makeshift bed by a broken toilet, around which is some ammo, chems, and cigarettes.