Yellowstone Mileage lets you calculate the shortest route & mileage between 2 end points in Yellowstone National Park (NP). The app is based on the Yellowstone NP map with squares added to indicate user-selectable points. These points are the park entrances, major intersections and campgrounds. You begin by touching one of these squares to select the origination point. Next you touch the square for the destination point. The app calculates the shortest route & mileage between these 2 points. Th