We recently drove on Route 66 also, the section between Victorville and Barstow, California.  One of the obviously old or “original Route 66” derelict buildings appeared at first to have been a gas station, but the way it’s laid out we don’t see where gas pumps could have been installed.  At first we thought the only door was the one with three steps to it.

When we studied the photo we discovered a boarded-up space perpendicular to the drive-through where there must have been a double door for customers.

The addition with two rather narrow doors on the end of the building must have been restrooms; we wonder how much plumbing was available!

Our guess is that this was a restaurant.  If you know this area, or more about the architecture of the time, please share with us!