If you have enough distance from any enemy or guard that is chasing you, you can lose them by running along the invisible boundary wall near the tops of mountain ranges. Run to as high up as you can on a mountain, then turn and run left or right along the invisible wall that prevents you from climbing any higher. NPCs have trouble running along this wall and this will slow them down. If you are far enough away from them (bow/crossbow range is acceptable), they will never catch up. After about a minute of running along this wall, your enemy will disappear and warp back to where they are bound.