David - I suggest you fire up Google maps and take a look at the territory between Las Vegas and Barstow - its not easy pickin's. I've looked at it some (its helpful to look at the Satellite image to see what the roads really look like). There's a brief stretch going SW out of LV where the UP tracks are sandwiched between I-15 and something called South Las Vegas Blvd - but most of that is some distance away (~couple of hundred feet) and then further SW, the tracks diverge from I-15 as you approach the CA-NV state line (I'll bet I-15 will be nutz...). Once in CA, the tracks go through the Mohave National Preserve. You will see a paved road that goes to Ivanpah, which intersects the UP tracks, but doesn't run parallel to them. Another bet, further west in the MNP is the Cima-Kelso road (looks paved) that does parallel the tracks between these two - uhhh - 'settlements'. One of the intriguing features of Kelso is a wonderful looking old station that seems to house a coffee shop (to serve about ten houses). From the map, you can click on the station and a Google street view will pop up! West of Kelso, the tracks go back into no-person's land almost until they parallel I-15 just east of Yermo.
As I said, I looked at this some and we've decided to head off in the other direction from Las Vegas - we're staying in Cedar City, UT and hope to see/chase the 4014 from Milford, UT to Caliente, NV (which has its own, absolutely classic, mission-style depot in the center of town). It also gives us the chance to go poke around in our favorite National Parks in SW UT - Zion, Bryce, Escalante-Grand Staircase.
