Year-Round Off Road Fat Truck Tours.  The Fat Truck is an amphibious- True All-Terrain vehicle, capable of traveling on Land, Water, Snow, Mud, or Frozen Lake and Tundra. An eco-friendly tour vehicle with only 2Lbs per square inch ground pressure, this Tundra-Friendly vehicle may look big, but it travels softly and safely, carrying guests off road to Vista Views and Wildlife viewing along mining/homestead trails near Denali just outside the Denali National Park boundary.