Here's a view out over Knott Rigg and Newlands Hause. Look at the sheep tracks on the side of the mountain. Sheep go sideways around the mountain mostly. They are not stupid in this regard and try to expend as little energy as possible. If they don't go up or down, they keep the same gravitational potential energy. Thus the sheep tracks could be called EQUIPOTENTIALS. I spend a lot of time drawing these for various types of force field. Incidentally, the force field lines are always at 90 degrees to the equipotentials. And since gravity points downwards, that is the case here. Sheep tracks look like well made paths and are a common reason for getting lost. Most horizontal paths in the Lake District mountains are not human made.
