Juniper Campground ($12), just inside the park’s northern border, is usually open year-round, with 94 sites. There are no hookups or showers—you’re directed to the Los Alamos YMCA up the hill instead. No reservations are taken, but it’s usually not full.
The scenery up on the plateau isn’t as striking as down in the canyon, but you will get an early start on the day if you stay overnight here.