JOSHUA TREE NATIONAL PARK, Calif. — Holiday crowds are jamming Joshua Tree National Park and authorities are urging visitors to have a backup plan, including other locations in the deserts of Southern California.

Park officials say wait times to enter the park can be as long as an hour and all campgrounds within Joshua Tree are full.

Officials recommend groups meet outside the park and carpool in one vehicle.

Visitors should also plan to arrive before 8 a.m. to avoid midday congestion, and consider all three entrances rather than just the west entrance where GPS devices often direct people.

Alternatives include public lands surrounding Joshua Tree as well as Death Valley National Park and the Mojave National Preserve.