Boardwalks direct people to the hot spots of the Upper, Midway and Lower Geyser basins. Odorous sulfur-infused steam wafts through the air. We see dozens of pools, boiling springs, bubbling mud pots and delicate formations of geyserite, a silicate mineral deposit. Steam rises from the enormous crater of Excelsior Geyser. The boiling vat releases 4,000 gallons of water a minute. Algae and bacteria color the Grand Prismatic Spring. Sounds — the constant hissing, gurgling, thumping, sighing and spitting — are as impressive as sights.

We end the day sitting by the huge stone fireplace of the Old Faithful Inn. The hotel is one of the largest log structures in the world, boasting a 76.5-foot-tall lobby. Electric candles softly illuminate lounging areas on overhanging balconies. Handsome, honey-toned gnarled logs form railings

Day Two

On a sparkle-fresh morning, we backtrack to West Thumb Geyser Basin and then follow the shoreline of Yellowstone Lake. The snow-crowned Absaroka Range fills the sky and reflects on the water.

We are too early in the season for a lake cruise or paddling excursion, so we hike through wetlands on the Pelican Creek Trail. A sign warns that this is prime bear habitat. Uprooted trees and shadowy shrubs under a dense canopy of pine have us imagining bears behind every rock. Back in our car, we follow the shore road to Mary Bay and Steamboat Point and then ascend to an overlook at Lake Butte. The sunset spreads its pink benediction over the largest alpine lake in North America.

Visitors at the Lake Hotel watch this twilight spectacle in period wicker furniture in the Sun Room facing Lake Yellowstone. Long ago, guests arrived by steamships, a more elegant way to travel than stagecoaches. The classic hostelry has undergone modernization, but still has the glamour of the past. In the elegant dining room, we enjoy a delicious meal of trout.

Constellations are astonishingly clear as we depart for our frontier cabin. Cheerful bedspreads, fluffy white towels and attractive furniture fill the dwelling. It is beautifully simple and, in that way, simply beautiful.

Day Three

The Yellowstone River flows north from the lake into the Hayden Valley. A road mimics the river's twists. Every turn presents a new viewpoint of the endlessly spectacular mountain vistas. Bison and elk herds graze in the sage-covered hills and lush meadows.

At the Grand Canyon of Yellowstone, tumbling water has carved out a 23-mile-long canyon. Yellow, orange and red in lasagna-like layers decorate the sheer rock walls.