In orienteering, you use a map and compass to locate a series of checkpoints shown on a specialized topographic map. You choose the route, either on or off trail, that will help you find all the checkpoints and get to the finish line in the shortest amount of time. Each checkpoint, or "control," is a distinct mapped feature such as a trail junction, a boulder, a hilltop, etc. The controls are marked with orange-and-white flags.
Orienteering is often called "the thinking sport" because it requires map reading, problem solving, and quick decision-making skills in addition to athletic ability and general physical fitness.