If you were riding your ATV you would want to avoid the steeper terrain. If undisturbed, game animals like deer are much the same, following the path of least resistance. If most of an area is relatively flat, they may travel anywhere. But in steep terrain, they’ll seek out flatter areas such as saddles between peaks, flat benches along hillsides and wider valleys.
Steep valleys or draws offer an excellent example. On a map, the perpendicular distance across a draw - from one hilltop to another - may seem minimal. It may be the shortest route, as the crow flies. But deer will be much more likely to take the longer route, walking roughly up parallel to the draw up to its head, where they will then switch back and walk down the other side, rather than crossing it perpendicularly.
Much the same is true of waterways or water bodies. Deer are good swimmers but they would just as soon avoid doing so if they can. They’re more likely to walk around a lake or pond than swim across it. They’re also more inclined to cross at the narrowest or shallowest section of a river. Again, look for where you would want to cross on an ATV and there’s a better likelihood of finding a game crossing.
Of course, there is one noteworthy exception to the similarities in ATVs and game activity. The best riding and the best hunting may occur where you find the same topographical features - the path of least resistance. But you’ll seldom find both in the same place.
Most game is intolerant of human disturbance. Ride as far as you can, then get out and walk to your final hunting destination, using your map to find the easiest route.