Last weekend we traveled 450 kilometers from Mendoza City to Valle Hermoso. You can go taking 40 and 144 route, and then the route 222. This place is known as Valle Hermoso (Beatiful Valley).
If you like to stay longer in this place, you have the chance to camp and see a beautiful sky in the night. First and last photo are from the camp. We stayed 1 night and we will back soon, you're basically alone there.