The Latenight Trail runs near the base of the mountains on the southwest portion of Red Rock NCA. They call it the Latenight Loop; not sure why as you need to ride one of the other trails to make a loop.
Start from the Latenight Trailhead and ride west, skirting Hwy 160. This part of the trail is less exciting than the rest - "gotta pay if you wanna play" I always say, it's a Vegas thing.
At the tunnel that connects 3 Mile Smile
to the south, steer north - this is where the fun begins. You'll enjoy the fruits of your labor for a good bit of downhillish fun. Enjoy the smooth, winding trail while you can for soon you'll be treated with some of the most excellent embedded rock gardens your imagination can conjure up. I would find it hard to believe that anyone could ride this whole trail without dismounting....but I've seen youtube. If it's hot, relish the few shade spots, or just ride when it's cool.
Ride the singletrack until you you reach the Black Velvet climbers' parking at the farthest NW area of the Cottonwood MTB trails. From here ride the rough jeep trail for a quarter mile, keeping a sharp eye for a hard right or easy left onto the Landmine Loop
trail where you'll sail on the smooth hard pack singletrack to any of the other fine trails in the Cottonwood Trail network.