YELLOWSTONE NATIONAL PARK, Wyo. (AP) — Yellowstone National Park will require an overnight backcountry permit fee starting May 1.

The National Park Service says the money raised from the new fee will help pay the costs of running the park's backcountry program. Under the new fee, anyone obtaining a permit to stay overnight in the backcountry between Memorial Day and Sept. 10 will have to pay a per-person, per night permit fee for all individuals 9 years of age or older.

Backpackers and boaters will pay $3.00 per-person, per night, with groups of 5 or more paying a total of $15 per night. Stock users will be charged $5.00 per-person, per night. Visitors may purchase an annual backcountry pass for $25.