In the early 2000s the availability of cheap GPS units lead to a new group of treasure hunters: Geocachers. The group used clues and GPS coordinates to find (and leave) small caches just about everywhere. Then, three years ago, bicyclists created a new category of ‘caching, Velocaching. The group kicked GPS and added two new tools: bicycles and photos. The photos give hints as to where the cache is while the bicycles help members find the generally urban-placed caches.