Stay at Big Bend of the Colorado Campground, near the shores of the Colorado River.
The river is cool and clear all year, so jump in for a refreshing swim! Boating is also popular, so bring your kayak. There are four miles of hiking trails nearby, or head west over the highway to undeveloped canyons and explore. Head back to camp in the evening, cook up some burgers on the barbeque, and spread out on the picnic area for a feast.