The Extended Tour

Closest entrances and distances: 40 miles from West Yellowstone (west) entrance; 38 miles from Gardiner (north) entrance; 48 miles from the Cooke City (northeast) entrance; 43 miles from the east entrance

You're in for yet another eyeful when you reach the Grand Canyon of the Yellowstone, which offers a vivid example of nature unleashing its destructive power to create indescribable beauty.

The canyon has its geologic origins in the same volcanic eruptions that created Yellowstone Lake. As lava flows created lakes that overflowed their banks, walls of granite-like rock remained while softer minerals eroded. This process carved the canyon, which was subsequently blocked by glaciers. Eventually, when the ice melted, floods recarved each end of the canyon, deepening it and removing sand and gravel.

The result: a 24-mile crevasse that at some points is 1,200 feet deep and 4,000 feet wide, and two waterfalls, one of which is twice as high as Niagara Falls. Even the most reluctant hiker will be rewarded with sites as colorful as those seen in "the other canyon." Compared to the Grand Canyon of Arizona, Yellowstone's Grand Canyon is relatively narrow; it's equally impressive, though, because of the steepness of the cliffs, which descend hundreds of feet to the bottom of a gorge where the Yellowstone River flows. It's also equally colorful, with displays of orange, red, yellow, and gold. And you won't find thermal vents in Arizona, but you will find them here, a constant reminder of ongoing underground activity.

You should plan on encountering crowds when you reach Canyon Village, where you'll find many necessary services: a post office, a trio of restaurants, and two stores stocked with groceries, gear, and souvenirs. Accommodations are in cabins and a large campground. Concessionaires offer horseback trail rides from a nearby stable and other guided tours.

The snazzy Canyon Visitor Center (tel. 307/242-2550) is the place to go for books and excellent exhibits on the park's geology, with a focus on the underlying super-volcano and receding glaciers. It's also staffed with friendly rangers used to dealing with the crowds here.

An auto tour of the canyon follows North Rim Drive, a two-lane, one-way road that begins in Canyon Village, to your first stop, Inspiration Point. On the way, you'll pass a 500-ton glacial boulder that was deposited by melting ice more than 10,000 years ago. Geologists estimate that ice floes carried this chunk of rock 40 miles to its present location.

At Inspiration Point, a moderately strenuous descent down 57 steps takes you to an overlook with views of the Lower Falls and canyon. (At 8,000 ft., the hike will cause your pulse rate and blood pressure to rise, so it's wise to pause for a few extra minutes before making the return.) Evidence of current earthquake activity is beneath the soles of your shoes. The viewing platform once extended 100 feet farther over the canyon; on June 30, 1975, it was shattered by an earthquake and tumbled into the canyon. There are several other viewpoints you can stop at along North Rim Drive before you reconnect with the main Canyon Village-Yellowstone Lake Road, which will take you down to South Rim Drive.

Along the way, you can also stop at Grand View overlook, where the river flows some 750 feet below the observation platform. During summer months, Grand View is an excellent spot from which to view ospreys, which normally nest in this area and can be seen riding the thermals. Lookout Point provides a better view of the Lower Falls; however, the observation deck is at the end of a steep, 150-foot trail. Going down is the easy part; the return trip is not recommended for those with heart or lung problems.

For the adventurous, an alternative to driving from one overlook to another is to negotiate the North Rim Trail, which is 2.3 miles long, beginning at Inspiration Point. This trail ends at the Upper Falls parking area, where the Upper Falls Trail begins; it's another .8 mile to the bridge that connects the North and South rims. Unfortunately, the North Rim Trail is not a loop, so if you take the hike, you'll have to backtrack to get your car at Inspiration Point. The footpath brings you closer to what you want to see, and you won't be fighting for elbowroom like you will at the overlooks that are a stone's throw from the road.

Whether you drive or walk, you should go down to the Upper Falls View, where a .3-mile trail leads down from the parking lot to the Brink of the Upper Falls, an overlook within splashing distance of the rushing river and the waterfall. At this point you won't just hear the power of the river, you'll feel it as it begins its course down the canyon.

The South Rim Road leads to several overlooks and better views of the Lower Falls. The most impressive vantage point is from the bottom of Uncle Tom's Trail, a steep 500-foot steel trail to an unbeatable vantage point that begins at the first South Rim parking lot. The trail is named after Tom Richardson, an adventuresome turn-of-the-20th-century guide who led travelers to the base of the falls with ropes and ladders; these days, the trip is down 328 steps of a steel staircase attached to the canyon wall and paved inclines. The trail is rather steep, but can be negotiated in about an hour, although it will be challenging for the neophyte hiker.

South Rim Road continues to a second, lower parking lot and a trail that leads to Artist Point. The view here is astounding -- one of my favorites in the park -- and is best in the early morning. It was at this point that Thomas Moran was inspired to create his famous painting of the falls, reproductions of which are seen in galleries and print shops throughout the world. This is one of the most photogenic (and most photographed) tableaux in the country -- almost every visitor snaps a shot or two.

The South Rim Trail is an alternative to viewing the Lower Falls and the canyon from wooden observation decks. From the first South Rim parking lot, which is just beyond the South Rim Drive Bridge, follow trail markers to the partially paved trail and then 1.8 miles to Artist Point. (The trail follows the canyon for 3.3 miles beyond Artist Point, to Point Sublime, where you must double back along the same route.) You'll have several different views of the falls, and you can always hop off to access Uncle Tom's Trail, Artist Point, and Lily Pad Lake. Neither Point Sublime nor Lily Pad Lake is accessible by car.