Situated between Black Buttes and Point of Rocks on Union Pacific's Rawlins Subdivision is the old station site of Hallville, WY. Not much denotes Hallville these days sans for the old station sign, what remains of the siding, and most uniquely the old US&S color light signal with 'blue light' extension. The blue light extensions, once somewhat common, are now all but extinct on the UP. The blue light extensions were once placed on signal masts that did not stand directly to the right side of the track which they governed. In this case the old intermediate here governs main track one, with the old Hallville siding in between the two, the blue light was an indication to anyone on the siding that the signal was not for them. Paying no mind to the unique signal on main one an eastbound auto train sails by on main two.
