For many, the views alone are worth the price of admission. But adventurers won't—and shouldn't—be satisfied with looking. Whether hiking down below the rim, floating through the Colorado River's alternating series of hair-raising rapids and cathedral-still quiet water, or marveling at the touch of two-billion-year-old rock under your fingers, it's interacting with this landscape that induces what writer Barry Lopez has called a unique "state of awe."

Raft the Colorado
When Powell and his crew of eight floated the Colorado River in 1869, they dreaded the stretches inside Grand Canyon, where walls of schist, gneiss, and granite made portaging impossible. After barely surviving a series of thundering rapids, Powell looked forward to exiting what he called his "granite prison." Today, commercial raft companies have turned Powell's "prison" into a 4,000-foot-deep (on average), 277-mile-long fun ride. You'll enter the canyon in durable rubber rafts instead of rickety wooden boats, eat gourmet food, and sleep under the stars or, during rainy weather, in a lightweight tent—all luxuries Powell never had. When not plunging through rapids, you can dry off, relax, and scan the rock walls for bighorn sheep. Best of all, you'll have a chance to explore many glorious side canyons, which branch out like capillaries from the gorge carved by the Colorado.

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Ride a Mule into the Abyss
Fred Harvey's immensely popular mule rides have been transporting visitors down into the depths for more than 90 years without major mishap, and are a central part of the Grand Canyon experience. The most memorable ones are the overnight trips to historic cabins at Phantom Ranch. The trip begins in early morning, at a corral south of Bright Angel Lodge. There, the wranglers deliver a pre-ride safety lecture that is funny enough to attract dozens of passersby. The mules also provide a chuckle or two: After departing the corral, they're skittish enough to be spooked by the sign at the Bright Angel Trail trailhead and dumb enough to occasionally back off of trails. Fortunately, they're also sufficiently cooperative to clatter along, nose to rump, from rim to river, avoiding any drop-offs they see. You'll descend the 4,410 vertical feet to the Colorado River on the lush (by Grand Canyon standards) Bright Angel Trail; spend a night or two in the cool, tidy, stone cabins at the ranch; then return on the dusty, panoramic, mostly manmade South Kaibab Trail. If the dust, heat, and barnyard smells don't take your breath away, the scenery certainly will.

Backpack to an Oasis
Leave the parking lots behind and lower yourself through craggy cliffs in the uppermost rock layer—the Kaibab Limestone—feeling the warm dust under your fingernails. You'll drift like an astronaut across the sun-blasted, cratered rocks on a platform called the Esplanade. You'll pass enormous red-rock boulders as you drop into Surprise Valley, where agave and blackbrush will scratch at your legs and trilling cicadas will seem to scratch your ears. Most seasons, the air will feel warm in your lungs, the sun hot on exposed skin. Just when you think the landscape couldn't possibly hold water, you'll see Thunder falls gushing from a cave in the Muav Limestone, then falling 100 feet. From here, you can follow Thunder River to Tapeats Creek, Tapeats Creek to the Colorado River, and a route near the Colorado to Deer Creek, where the spring-fed creek has carved a smooth, fluted section of narrows.

Take a Learning Vacation
Though the average visitor stays only a few hours at Grand Canyon, naturalists, geologists, archaeologists, and other assorted canyon enthusiasts have spent lifetimes studying the land in and around the park. Some of the foremost canyon scholars now teach for the Grand Canyon Field Institute, a not-for-profit organization dedicated to helping visitors appreciate the natural and human history of the canyon. On the Field Institute's rim-to-rim natural history backpacking trips, for example, the instructors share a world of information. And whether it's describing the history of the Bright Angel Trail, pointing out features of the canyon's six life zones, or telling an incredible geologic tale that culminates in the 2,000,000,000-year-old Vishnu Formation—some of the oldest exposed rocks on earth—you'll leave with a much richer understanding of the natural history of the canyon, and of the earth itself.

Day Hike to Dripping Springs
Walk a quarter-mile along the rim from Hermit's Rest to the trailhead for the Hermit Trail and the crowds begin to thin. Dropping below the rim, you'll descend in gradual switchbacks en route to the broad expanse of upper Hermit Basin. As you set foot on the crumbly red Hermit shale, you'll smell the piney scents of pinyon pine and Utah juniper and feel the heat rising from the sun-warmed rocks. You may feel vertigo while crossing above 800-foot cliffs at the head of Hermit Creek canyon. Then you'll climb toward an amphitheater at the head of a small side canyon below Eremita Mesa. When it appears that you can't go farther, you'll smell moisture and see water dripping from a sandstone overhang into the stone-bordered pools below. By now you're more than three miles from the rim—farther than most people walk into the canyon, and a world away from the busier trails. Before turning back, you'll want to take a few moments to rest, listen to the cries of ravens, and cool off in the shade under the overhang.

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