The engine number is obscured, but this late model Southern Pacific cab-forward is sticking its nose out of a dead-end tunnel.   Say-what..? The location is Cascade Summit on the line from Eugene to Klamath Falls, Oregon. 

A helper district from Oakridge ended here at the summit. The helpers were cut off and turned on a wye for the return trip downhill. The problem here at Cascade Summit was cramped space, and a turning wye requires a fair amount of real estate to function.

Problem solved, burrow a tunnel long enough negotiate the movement.  The track leading out of the picture to the left links up with the Westbound mainline towards Klamath Falls.  The other towards Oakridge and Portland.  .  A turntable was impractical unless covered, and snowplows easily keep the wye clear.  To my knowledge this arrangement is unique to the Southern Pacific.   Photo and caption submitted by Gary Ostlund.