A monster truck is made for rough roads and that is why, you don't normally see them on the road. They are built to be driven on those rocky mountains that has no roads on them. Most of the time, the roads aren't concrete as they are built from mere dirt. It only serves as a guideline to the vehicles trying to get to the city. The mountain is the last thing that a government want to build a road since it is much too expensive because of the slope of the mountain. Most machinery would have a hard time going there. Manpower will also cause some problem as only a handful of men would be willing to work in such environment. It is dangerous. But, that doesn't mean that no one or no vehicle could drive there. Monster truck can certainly live to the task and that is why there are made especially for that kind of surrounding.
Drive your truck as fast as possible so you can reach the finish line in the least possible time. Make sure that you won't fall on your back while driving your truck. Time is not that important in this game so you can take as much time as you want.