dozen or so miles out of town, we pass cyclists and even a jogger taking it in. Had Carmen not already added Jackson to her must-return list--a sentiment I echo--the prospect of riding her bike along that 100-mile stretch of U.S. 89 to Yellowstone would have sealed the deal.

Farther on, a herd of bison stops traffic for at least 20 minutes as they amble across the road. As if protected by shatterproof glass and electric fences, people from other cars approach the enormous beasts with their cameras. One woman's flash goes off, and the closest animal stops in its tracks to stare. I fear The Boy will get a lesson about "Nature, red in tooth and claw" that I'd rather he didn't quite learn yet. The creature eventually turns and gallops ahead.

Hoping to see Old Faithful in light conducive to taking photos, we head straight there once inside the park, enjoying the meandering 39-mile drive free from the summer crowds. Not all concession areas are open this early in the season, so the parking lot adjacent to Old Faithful and the large visitor center is quite full. Chaucer is one of at least half a dozen dogs visiting this world-famous attraction. The Boy, of course, is thrilled with the loud waterworks display.

For our two nights inside the park, we had booked one of the pet-friendly Lake Yellowstone Cabins. Built in the 1920s (with extensive remodeling completed in 2004), these comfortable duplex cabins clustered near the historic Lake Yellowstone Hotel are open May to October. By chance, our arrival is just a day after they open. Although temperatures continue in the low 60s during the daytime, late-spring snow lingers on the lakeshore, and we are pleased when