Orienteering usually requires specially produced maps drawn at scales which show a high level of detail.
Wherever it occurs, orienteering usually involves visiting pre-designated places (called Controls) in a particular order. Orienteering involves thinking carefully about your route. Sometimes it will be quickest to go round paths; sometimes the faster route is a more direct one across rougher ground.
The Adur Centre has a number of orienteering courses in Sussex, Surrey and Hampshire. These are a great way to try orienteering out without going to a formal event.