Inside the park on the South Rim, cyclists are allowed on all paved and unpaved roads where motorized vehicles are allowed as well as on the Greenway Trail. The new paved Greenway Trail now connects the Grand Canyon Visitor Center with Pipe Creek Vista (1.3 miles) and the trail head of the South Kaibab Trail (another .8 miles). New sections of the Greenway Trail will be open in late spring 2012 connecting the Grand Canyon Visitor Center with the campground and on to the gateway community of Tusayan. Most of the Tusayan Trail will be unpaved. Cyclists are not permitted on hiking trails below the rim or pedestrian paths, including the rim trail between Mather Point and Monument Creek Vista. Hermit Road is open to cyclists year-round and makes for a terrific ride, but you'll need to yield to tour buses, shuttles, private vehicles, and people on foot.

On the North Rim, the entrance road is wide enough to accommodate experienced cyclists, and bicycles are permitted on all blacktop roads, as well as the Arizona and Bridle Path trails.

Outside the park, experienced cyclists enjoy the spectacular views on Highway 67 (from Jacob Lake to the North Rim entrance) and the ride on Highway 89 (from Fredonia, Arizona, to Jacob Lake), which travels through several climates.

Bicycles are now available for rent on the South Rim (except for in winter) at a temporary facility next to the Grand Canyon Visitor Center. A permanent bike rental and snack shop building should be open here by summer 2012. On the North Rim, there is a bike rental shop at the Sinclair Gas Station by the entrance to the North Rim Campground. When planning a ride, keep in mind the high altitude.

Mountain Biking

To mountain bike near the Grand Canyon, you'll need to cross out of Grand Canyon National Park into the Kaibab National Forest, which borders the park on both rims.

On the North Rim, avid cyclists flock to the Rainbow Rim Trail, an 18-mile stretch of single track (no motor vehicles allowed) that provides access to five remote canyon overlooks. Old logging roads, jeep trails, and footpaths crisscross other North Rim areas, providing a variety of cycling options. Visit the Kaibab Plateau Visitor Center in Jacob Lake (tel. 928/643-7298; www.fs.usda.gov/kaibab/recreation) for directions, maps, road conditions, and trail descriptions.

On the South Rim, you'll find excellent mountain biking on the trails around the Grandview Fire Tower. To reach the tower, take Highway 64 east from Grand Canyon Village. About 1 1/2 miles east of the Grandview Point turnoff, turn right (south). Leaving the park, follow this dirt road 1 1/2 miles to Grandview Fire Tower and the trail head. Beginning here, you can ride more than 20 miles of intermediate-level single-track (with a few short, technically demanding stretches), much of it along the Coconino Rim.

Another trail system, with loops of 3.7, 10.2, and 11.2 miles, is near Tusayan. These loops follow old jeep trails through rolling hills in the ponderosa pine forest and have a few steep, rocky areas, though most of the terrain is only moderately difficult. To reach them, find the marked parking area 1/3 mile north of Tusayan on Highway 64's west side. A single trail goes north from there, eventually crossing under the highway through a concrete tunnel and providing access to the loops. (Note: This is also a great place to run when staying in Tusayan.) For information on these trails and maps of the Tusayan Ranger District (tel. 928/638-2443), visit the Forest Service office (weekdays 8am-4:30pm) a half-mile south of the park entrance on Highway 64.

Bike Rentals

Bicycles can now be rented on the South Rim from Bright Angel Bicycle Rentals and Tours (tel. 928/814-8704; www.bikegrandcanyon.com). In addition to bike rentals, they offer guided tours and also provide shuttle service along Hermit Road for those who prefer a shorter bike ride. Adult bikes cost $10 per hour, $25 for a half-day (4 hr.), and $35 for a full day; cost for children under 18 is $7, $15, and $25, respectively. Located next to the Grand Canyon Visitor Center, the rental shop is open from 8am to 6pm in high season. The company offering bike rentals on the South Rim could change in 2012.

For the South Rim, higher-end bicycles can be rented in Flagstaff at Absolute Bikes (tel. 928/779-5969), 202 E. Route 66. Prices vary from $20 to $70 for a full day, $20 to $60 for a half-day.

On the North Rim, Forever Resorts (tel. 928/638-2611, ext. 758) rents mountain bikes at the Sinclair Gas and Outfitter Station located at the entrance to the North Rim Campground. Adult mountain bikes cost $40 per day or $8.50 per hour; kid-size mountain bikes cost $25 per day or $4 per hour. Helmets are required and provided.

Outside the park, Escape Adventures (tel. 800/596-2953 or 435/259-7423; www.escapeadventures.com) in Moab, Utah, offers mountain and road bike rentals on a half- or full-day basis. Mountain bikes range from $35 for a half-day to $75 for a full day. Road bikes cost $55 for the first day, $45 for each additional day. For $225, you'll get a road bike for 7 days. Escape Adventures also offers multiday mountain bike tours of the North Rim; call or see the website for seasonal rates.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.