This driving adventure follows the White Rim below the sheer cliffs of Island in the Sky. A close look at the light-colored surface reveals ripple marks and crossbeds laid down near an ancient coastline. The plateau's east side is about 800 feet above the Colorado River. On the west side, the plateau meets the bank of the Green River.

Travel along the winding road presents a constantly changing panorama of rock, canyons, river, and sky. Keep an eye out for desert bighorn sheep. You'll see all three levels of Island in the Sky District, from the high plateaus to the White Rim to the rivers.

Only four-wheel-drive vehicles with high clearance can make the trip. With the proper vehicle, driving is mostly easy but slow and winding; a few steep or rough sections have to be negotiated. The 100-mile trip takes two or three days. Allow an extra day to travel all the road spurs.

Mountain bikers find this a great trip, too; most cyclists arrange an accompanying vehicle to carry water and camping gear. Primitive campgrounds along the way provide convenient stopping places. Both cyclists and four-by-four drivers must obtain reservations and a backcountry permit ($30) for the White Rim campsites from the Island in the Sky visitor center. Find application forms on the Canyonlands website; return the completed application at least two weeks in advance of your planned trip. Questions can be fielded via telephone (435/259-4351, 8 a.m.-12:30 p.m. Mon.-Fri.), but no telephone reservations are accepted.

Demand exceeds supply during the popular spring and autumn seasons, when you should make reservations as far in advance as possible. No services or developed water sources exist anywhere on the drive, so be sure to have plenty of fuel and water with some to spare. Access points are Shafer Trail Road (from near Island in the Sky) and Potash Road (Hwy. 279 from Moab) on the east and Mineral Bottom Road on the west.

White Rim sandstone forms the distinctive plateau crossed on the drive.