Even Jack London couldn't have penned a better northern wilderness setting than Alaska and British Columbia's Alsek/Tatshenshini watershed. Throughout the river's 157 miles, be ready to encounter everything from wolves, moose, bear, and salmon to giant blue-ice glaciers and icebergs the size of the Titanic. Above all, however, be ready for solitude—the only sounds you'll hear will come from the rumbling of glaciers, and the only lights you'll see will be from the campfire, stars, and aurora borealis high overhead.

The first recorded descent of the Tatshenshini was made in 1890 by English explorer Edward James Glave, with companions Jack Dalton, who later pioneered the Dalton Trail from Haines to the Yukon, and two Tlingit Indians. Most of today's trips start at Jack's namesake Dalton Post, about 100 miles from Haines, Alaska, and cover the river's 157 miles in seven to eight days.

Although the rapids on the Tatshenshini rate only Class III, the scenery is another matter entirely. The Alsek and Tatshenshini cut through the heart of the St. Elias Range, one of the largest coastal barriers of peaks and glaciers in the world. The first few days on the Tat traverse wooded valleys and two steep-walled canyons. As the river approaches the St. Elias range, however, its character changes. Temperatures drop and rain increases due to storms trapped by the coastal mountains, and the river's volume starts to swell as glacier-fed side streams pour in from all directions. At mile 98, the river's character undergoes an even more dramatic change as the Alsek thunders in from river right, causing the distance from shore to shore to approach three miles in places and the current to pick up to as much as 9 mph. (The Alsek itself is rarely run, due to an ominous four-mile chasm known as Turnback Canyon.)

Below this confluence is when you'll start to see icebergs—some of which top out at 75 feet high—from huge, plateau glaciers creeping up to the river's edge. If you're lucky, you'll also catch a glimpse of 15,300-foot Mt. Fairweather 35 miles to the southeast. Camping from here on can be tricky, as boats often have to be pulled up high enough to escape waves caused by calving glaciers. The end comes all too quickly, like with that Jack London story, as you reach Dry Bay on the Pacific where an awaiting float place whisks you back to the village of Yakutat.

Difficulty: Class III, but you don't want to swim. The water is glacier cold, and once the Alsek pours in, it can be a long swim to shore.

Price Range: The scenery is expansive, the trip expensive. Still, the $2,250 price tag for a 10-day trip isn't too bad when you consider it includes a bushplane charter pick-up and the drive to the put-in.

Best time to go: June to mid-September.