Rafting

The best way to experience the geologic depths of Dinosaur National Monument is to take a white-water rafting trip on the Green or Yampa River. Joining forces near Echo Park in Colorado, the two waterways have each carved spectacular canyons through several eons' worth of rock, and contain thrilling white-water rapids. River-running season is typically May through September. Permits are required for all boaters.

Adrift Adventures. The closest guide service to the Dinosaur National Monument, this outfitter offers one-day or multiday rafting trips on the Green and Yampa rivers. Note that a pass to Dinosaur National Monument must be purchased separately beforehand. 9500 E. 6000 S, Jensen, Utah, 84035. 435/789–3600; 800/824–0150; www.adrift.com. From $109 (day trip, including lunch).

Dinosaur River Expeditions. The only locally owned outfitter in Dinosaur National Monument, this company offers daily and multiday whitewater trips on the Green and Yampa rivers. Guided hikes are also offered that can take you to petroglyths, rock formations, and dinosaur footprints, depending on the route. 2279 N. Vernal Ave. , Vernal, Utah, 84078. 800/345–7238; www.dinosaurriverexpeditions.com. From $95.

OARS Dinosaur. In operation since 1969, OARS offers one-day and multiday rafting trips on both calm and white waters on the Green and Yampa rivers. 221 N. 400 E, Vernal, Utah, 84078. 800/342–8243; www.greenriverrafting.com. From $109.