While you'd be hard-pressed to come up with any bad hikes in Glacier, the best ones are generally up on the Continental Divide. Case in point: the four-day, 21-mile trek from Cut Bank trailhead to Two Medicine in the southeast of the park. From Cut Bank, hike four miles to Atlantic Creek Campground and do some fishing in Medicine Grizzly Lake. If you're lucky, you'll come away with a dinner of rainbow trout. Take a layover day to hike three miles to Triple Divide Pass; the peak directly southwest is the only place in the nation where water drains into the Atlantic, Pacific, and north into Hudson Bay. From there, proceed along talus slopes to Morning Star Campground. Day three takes you over Pitamakan Pass and Dawson Pass, where you should ditch your load to dash up nearby Flinsch Peak (9,225 feet). End the day at No Name Lake. The final hike out to the Two Medicine North Shore trailhead traces the edge of Two Medicine Lake, where you have the option of snagging a lift on a tour boat ($11.25) for the final few miles. After all, you've earned it.
Backcountry permits are required for overnight hikes ($5), and campsite reservations are recommended ($30; nps.gov/glac/planyourvisit/backcountry.htm has forms). Glacier Park Boat Co. runs ferries on Two Medicine Lake (glacierparkboats.com).
If the dire projections are correct, Glacier National Park will be bereft of glaciers by 2030. So get going. High above the milky waters of Grinnell Lake, Grinnell Glacier is the most stunning in the park. It's accessible via a boat trip across Swiftcurrent and Josephine Lakes, then a 3.8-mile hike.
Due to its Matterhorn-like peaks, the park's Many Glacier area has been dubbed the "Swiss Alps of America"—a theme the Many Glacier Hotel runs with. The chalet-style lodge lays on such touches as afternoon fondue and a Heidi-themed gift shop. Frankly, the overly Alpine atmosphere can be a bit cloying, but you can't argue with good rooms in a great location (doubles from $142; glacierparkinc.com).
Originally published as part of "America's Ultimate Parks 2009," National Geographic Adventure magazine