About 100 rivers begin in the Canadian Rockies. Clear, icy flows from melting glaciers trickle down the mountains, creating headwaters to rivers that feed into three oceans: the Atlantic, the Pacific and the Arctic.

The thousands of lakes here take on every color in the blue-green spectrum. The unique shades are created as sunlight hits the water and reflects off suspended particles of rock, which has been ground into dust by the movement of glaciers.

The color of any particular body of water is determined by the different sizes and mineral contents of those "rock flour" particles. The shades are so unusual that on my return from a trip to the Canadian Rockies last summer, I consulted paint charts for help in naming them. Some of the best matches: jargon jade, calypso, rapture blue, emerald, Aegean.

Summer days are long, with up to 17 hours of sunshine, yet temperatures tend to hover in the 70s.

Not convinced yet that the place is worth the long trip?

Consider the waterfalls that thunder into deep green pools and explode against protruding rocks. Tiny sprays of water droplets collide with beams of sunlight, creating constant flickers of rainbows.

Or the snowcapped mountains that in a certain light are mirrored in still lakes, making it appear as if earth, water and sky have become one.

Hollywood discovered the Canadian Rockies before the moving pictures had sound. Many times, these mountains have been stand-ins for the Swiss Alps. Many of the pictures floating around our minds of the wild American West are actually images of the Canadian Rockies.

SAMPLE THE CALL OF THE WILDERNESS AT NATIONAL PARKS

When it comes to the Canadian Rockies, the question is not whether to put this area on your travel wish list, but which part of the vast territory to tackle.

Four contiguous national parks — Banff, Yoho, Jasper and Kootenay, all UNESCO World Heritage sites — lie within the provinces of Alberta and British Columbia, and are surrounded by millions of acres of wilderness areas, forest reserves and provincial parks.

After much deliberation, I chose Banff National Park. After flying to Calgary, 80 miles southeast, I could hit many of the park's highlights in less than a week, plus a piece of Kananaskis Country (a rural area west of Calgary) and a tiny slice of Jasper National Park.

'BROKEBACK MOUNTAIN'

Horses have never been known to commit suicide, have they? That's what I'm thinking as we ride just a few feet from a cliff that towers at least 100 feet above the Bow River. None of the horses had shown any signs of depression as we left the Kananaskis Guest Ranch, and now they're walking calmly. I soon forget my apprehensions and lose myself in the beauty of the landscape. The river below, famous for harboring trophy-size trout, is an alluring milky blue, surrounded by tall evergreens.

When I booked this ride before leaving home, I worried that I was making a mistake; maybe I should have gone all the way into Banff National Park to ride. Millions of people from around the world head straight to Banff. This area, 45 minutes from Calgary, is popular with locals, but maybe they just don't want to travel the extra distance to the park.

But now I'm congratulating myself. We wind along the river, then trot up the side of a mountain into a broad grassy meadow. The trail leader announces that "Brokeback Mountain" was filmed here. If you've seen the movie, you know how beautiful and peaceful the landscape is.

A short distance away, I settle into the Rafter Six guest ranch, where I'll spend the night. After tucking into a huge lunch, I walk a few yards to the barn and volunteer to groom horses. The place is a find. I soon meet owner Stan Crowley, who tells me the ranch was a remount center for the Canadian Mounties in the 1800s, and before that, an outfitters post.

The walls of a lounge area in the log lodge are covered with autographed pictures of some of the luminaries who have stayed here. So many Disney films were shot here, beginning in the 1940s, that the former owners built a cabin just for Walt.

Next morning I tug on a wet- suit for what turns out to be the best rafting trip I've ever taken. Why? In part, the wild enthusiasm of the young guides, in part the scenery, in part the rush of being splashed by ice-cold water that, given the heat of the sun, felt great. But most of all, it was the free rafting. That's a name I made up: It involves getting out of the raft and riding the rapids on our backs, feet forward, with a promise that we'd be helped out of the water when the rapids pooled.

SHOPS, DINE AND SEE

Since it sits in the midst of a national park, I was expecting Banff to be somewhat rustic. Instead I find a busy center of chic stores and restaurants, and low-rise lodgings and museums. The Whyte Museum houses a huge collection of art and artifacts relating to the Canadian Rockies. There's also a national park museum, restored in 1985 for the park's 100th anniversary, a museum of natural history and a museum of Plains Indians.

That evening, I drive outside town to visit the hot springs. The place has a fascinating history, but I'm somewhat disappointed that the steaming water is held in a large but ordinary swimming pool, and the view is blocked on two sides by a bathhouse akin to a YMCA.

Next morning, as I drive north along the Bow Valley Parkway in a rush to reach famed Lake Louise (about 30 miles from downtown Banff), I almost decide to pass by Johnston Canyon. I'm glad I didn't.

True purists may object to the paved paths, but the waterfalls and "ink pots" — mineral springs that are a brilliant aqua color — make up for the pavement.

Water has been eroding the canyon for 8,000 years. A plaque notes that "when the pyramids were being built, the canyon was only half as deep as today." The waterfalls are small but beautiful. Most people stop after the first fall, about half a mile from the parking lot. But you find solace if you go another mile to a second waterfall, then on to the ink pots.

My only regret is that I arrive at Johnston Canyon early in the day, so I am not able to have lunch at a charming little restaurant whose deck reminds me of a rural German beer garden. But I'm mollified with a picnic later along the shores of Lake Louise. The famous lake is smaller than I'd imagined — 1 1/2 miles long and 1,600 feet wide. But what it lacks in size it makes up for in beauty.

At one end is the towering face of the 11,350-foot-tall Mount Victoria, which straddles the Continental Divide. The elegant Fairmont Chateau Lake Louise sits at the other end, its manicured gardens a draw for both tourists and moose. The other two sides of the lake are lined with trees and hiking trails, one of which leads to a teahouse.

Even if you can't afford to stay the night, splurge on a meal or tea in one of the restaurants that overlook the lake, and check out the shops. At a gems store I covet an amazing artwork of nature: a slab of rock with indentations from a fossilized palm tree and several fish, arranged as if by the hand of a genius artist.

I splurge on a $30-an-hour canoe rental. (All prices quoted are in U.S. dollars.) Learning that the lake is up to 295 feet deep and never gets warmer than 39 degrees, I'm glad it's rather small.

I further enjoy the beauty of the lake on the outdoor patio of one of the hotel's two cheapest restaurants, the Glacier Saloon. Given the views, it's a bargain, even though the food is ordinary, with entrees ranging from about $12 to $24.

There are a couple hours of daylight left, and I wonder if I should drive about 16 miles to Moraine Lake. I'm spending the night here at Lake Louise, which is by far the most visited and most famous lake in the Canadian Rockies, so why not relax here?

But I head off. The deep blue waters of Moraine Lake are sheltered by mountains, and the lake is accentuated by an island covered with tall, green trees. I am the only person sitting along the shore awaiting a sunset that makes the land and water glow.

AN INSPIRED STOP

It's a 114-mile trip from Lake Louise to Calgary, where I need to be for an early-morning flight the next day. The big question: Should I add a visit to the Columbia Icefield, 80 miles in the opposite direction from Calgary?

I really don't even know what an ice field is, but I head there, making stops along the way. One stop — Num-Ti-Jah Lodge — turns out to be inspired.

The log lodge along the Caribbean-colored Bow Lake was built by Jimmy Simpson, who left England in 1896 as a teen and set out for the Canadian Rockies. He became a famous guide, and in the early 1900s began building the lodge, using logs that were 75 feet long. You can feel the history and romance when entering the lodge.

After a lunch of herb-crusted salmon, I walk around the lake and chat with a park-service worker. He tells me an ice field is more or less a glacier, only bigger, and recommends I hire a guide to hike it.

Turns out that unless you're lucky, you have to reserve a guide in advance, so I board a vehicle that would be a little boy's dream: a lumbering thing developed for arctic exploration. After about 15 minutes, it drops me at an area bounded by orange cones and tape, lest visitors wander and fall into a crevasse.

The ice field lies within both Banff and Jasper national parks, and for a moment I'm tempted to venture a bit farther into Jasper than I've already come. But I have more than 200 miles to go before I sleep. I'm confident that while I might have missed something, I've sampled at least some of the best.