The DeLorme Challenge is named after the DeLorme Atlas and Gazetteer. DeLorme publishes an atlas for each of the fifty states, dividing it up into 50-100 pages. The challenge is to find or hide a cache on each page of a state's atlas. Once this requirement has been completed, the owner of the special Challenge Cache with email the coordinates of the final container to the cacher.
The rules for the challenge vary from state to state. With some exceptions, the general rules are:
- Caches found prior to the start of the challenge, including archived caches, are allowed.
- Locationless and event caches are usually excluded.
- Most states allow the placement of a cache priot to the start of a challenge to count as completing a page.
- Pages along the border of a state may include land from neighboring states. Only caches found in the challenge state count.
- On atlas pages with inset maps, some states require a cache to be found on both the main part of the map and in the inset, others require only a single cache anywhere on either map.
The following states have DeLorme Challenge caches set up: