Since the Canadian Pacific Railway built its famous mountain lodges and started drawing eastern tourists to the west in the 1920s, these two parks have been at the center of alpine outdoorsmanship.

With decades to cultivate the industry, it's now exceptionally professional, well-developed, and full of abundant choice. If you're staying in Banff, Jasper, or Lake Louise, you'll find that outfitters and rental operations are sophisticated and make it easy and convenient to get outdoors. Most hotels offer a concierge service that can arrange activities for you; for many, you need little or no advance registration.

If you're not the kind to tromp out into the wilderness, fear not: You don't even have to break a sweat to enjoy the magnificent scenery. Hire a horse and ride to the backcountry, or take an afternoon trail ride. Jasper, Banff, and Lake Louise have gondolas to lift travelers from valley floor to mountaintop. Bring a picnic, or plan a ridge-top hike. If you're not ready for white water, the scenic cruises on Lake Minnewanka and Maligne Lake offer a more relaxed waterborne adventure.

Biking

Both parks provide free maps of local mountain-bike trails; the Bow Valley Parkway between Banff and Lake Louise and Parkway 93A in Jasper Park are both good, less trafficked -- and staggeringly beautiful -- roads for road biking. Bike rentals are easily available nearly everywhere in the parks.

Rock Climbing, Ice Climbing & Mountaineering

The sheer rock faces on Mount Rundle near Banff, and the Palisades near Jasper, are popular with rock climbers, and the area's many waterfalls become frozen ascents for ice climbers in winter. Instruction in mountaineering skills is offered by Yamnuska Inc. Mountain School, based in Canmore (tel. 403/678-4164; www.yamnuska.com).

Skiing

Banff and Jasper offer some of the best skiing in the world; in Banff, Sunshine Village and Lake Louise are two huge ski areas, with Louise being the larger of the two, and the most scenic; Sunshine, still huge, has less skiable terrain, but is above the tree line, and tends to have more snow, and deeper into the season -- sometimes all the way to June. Mount Norquay, just above the town of Banff, is much smaller, but steep and challenging; it's also the only one to offer night skiing. Jasper, meanwhile, has Marmot Basin, a lovely mid-size ski area that doesn't get anywhere near the traffic of the Banff resorts -- a plus for that alone.

Wherever you go, skiing here can be superb: The snowpack is copious, the scenery beautiful, après-ski festivities vibrant and occasionally wild, and accommodations world-class. Lift tickets are generally cheaper than at comparable resorts in the United States.

Heli-skiing isn't allowed in the national parks but is popular in the adjacent mountain ranges near Golden in British Columbia. CMH Heli-Skiing 217 Bear St., Banff (tel. 800/661-0252 or 402/762-7100; www.cmhski.com) is the leader in this increasingly popular sport, which uses helicopters to deposit skiers on virgin slopes far from the lift lines and runs of ski resorts. CMH offers trips that last anywhere from two to 10 days, to 12 locations; prices begin at C$5,500 including lodging, food, and transport from Calgary.

White-Water Rafting & Canoeing

The Rockies' many glaciers and snowfields are the source of mighty rivers. Outfitters throughout the region offer white-water rafting and canoe trips of varying lengths and difficulty -- you can spend a single morning on the river, or plan a 5-day expedition. Jasper is central to a number of good white-water rivers. Maligne Rafting Adventures Ltd. (tel. 780/852-3370; www.mra.ab.ca) offers packages for rafters of all experience levels.

Wildlife-Viewing

Banff and Jasper are great places to see alpine animals in the wild, from hundreds of species of birds to large mammals. Both parks teem with wildlife -- bighorn sheep, grizzly and black bears, deer, mountain goats, moose, coyotes, lynxes, wolves, and more.

Park Wildlife & You -- The parklands are swarming with wildlife, with some animals meandering along and across highways and hiking trails, within easy camera range. However tempting, don't feed the animals and don't touch them. You can be fined up to C$500 for feeding any wildlife, for one thing. For another, it's extremely dangerous.

As docile as some of these animals may seem as they take your handouts, you have to remember: These are wild creatures for whom the first rule is survival. If they feel threatened, they will either run or attack.

And while they can seriously hurt you, you might be doing the same to them. It may be hard to say no to some of these hungry, big-eyed creatures, but your kindness can kill them. Bighorns, for one, get accustomed to summer handouts of bread, candy, potato chips, and marshmallows when they should be grazing on the high-protein vegetation that'll help them survive through the winter.

Moose, meanwhile, can quickly become unwanted guests. A kindly offered snack can quickly become an invitation to take over an entire picnic, and once a moose has decided that's what he or she wants, you won't be able to say no: They sometimes weigh well over a ton.

During elk calving season, some trails will be closed to hikers for their own safety. A new mother elk is quick to take any nearby activity, however innocent, as an imminent threat to her newborn calf. Surprising a mother and calf could also result in a panic that separates them, sometimes for good.

Then there's bears. Both black and grizzly bears call the parks home; grizzlies, at up to 2m (6 1/2 ft.) on their hind legs, are the more threatening of the two, but don't underestimate the grizzly's smaller cousin, the black bear, which is relatively small at 1.5m (5 ft.) long. Both can be very dangerous when startled or threatened; your best bet is to make plenty of noise on the trails as you walk (singing and clapping your hands work well) to let them know you're coming.

The grizzly spends most of the summer in high alpine ranges, well away from tourist haunts. As one of North America's largest carnivores, its appearance and reputation are awesome enough to make you beat a retreat on sight. But the cuddly looks and circus antics of the black bear tend to obscure the fact that these too are wild animals: powerful, faster than a horse, and completely unpredictable.

Hiking in bear country (and virtually all parkland is bear country) necessitates certain precautions; ignore them at your peril. Never hike alone and never take a dog along. Dogs often yap at bears, then when the animal charges, they run toward their owners for protection, bringing the pursuer with them. Above all, never go near a cub. The mother is usually close by, and a female defending her young is the most ferocious creature you'll ever face -- and possibly the last.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.