From the North Woods to the Rockies, the railway lets you swallow North America whole

THEY stood at a lonely spot called Craigellachie in the mountains of British Columbia, on the 15th of November in 1885. The name of the place was Scottish, as were a good many of the men gathered at trackside. They watched as Donald Smith, who had yet to become Lord Stratchcona, drove an iron spike that finished the thing they had built -- the Canadian Pacific Railway (CPR). Most Americans are aware of the driving of their own golden spike in 1869 at Promontory, Utah, as one of the pivotal events in the nation's history. For Canada, though, the completion of the transcontinental railway was arguably the pivotal event. The spike that linked the eastern and western segments of the CPR riveted together the 18-year-old nation as well.

Not coincidentally, the completion of a railroad from the St. Lawrence Valley to the Pacific opened up one of the most scenic tourist routes in the world, one which today's travelers can still enjoy in comfort. The Canadian Pacific has turned over its passenger operations to Via Rail Canada, a government corporation that is roughly the equivalent of Amtrak in the United States. But the daily transcontinental Canadian remains on a par with the great long-distance trains, legends like Amtrak's Empire Buil der and the Australian Railways' Indian Pacific.

The Canadian is not an adventure in extravagance like the restored Orient Express or South Africa's Blue Train, or even the Canadian Pacific limiteds of yore, which offered more choices in marmalade than today's trains have dinner entrees. Most of the rolling stock dates from the mid-'50s, the Indian summer of art deco streamlining: the lucite railings on the stairs between the lounge and the observation level actually light up at night. But the old cars are decently maintained, the beds in the sl eeping compartments are comfortable, and linen still covers the dining tables. It all adds up to a pleasant, if not opulent, backdrop to the main attraction, which is nothing less than North America.

There is no better way than a 3,000-mile train trip to learn what this continent really looks like. Even if the clouds part, you can't get the picture from 30,000 feet; and as for driving, the sheer distances involved make the experience more of an endurance test than a revelation. No, the train is the way, and as fond as this traveler is of the change-at-Chicago American routes, the Canadian is the one that makes you feel as if you're swallowing North America whole.

The question of whether it works better from east-to-west or west-to-east might seem answerable only in terms of where you happen to be when you start out, but a case can be made for embarking from Montreal or Toronto (the train leaves every afternoon) and heading west. It all has to do with the way the topographical story unfolds and climaxes; the mountains are out west, and if you start in Vancouver you're watching the last act first.

The east-west run takes you through the suburbs of Toronto and the lake country of southern Ontario in darkness. When you slide open your window shade, you'll be in the vicinity of the much-maligned smelting town of Sudbury, but the slag heaps soon fade away and the immensity of the North Woods begins.

The North Woods -- pines, birches, and a hundred-thousand lakes, serve as reminders that one-third of all the fresh water in the world is in Canada. The woods overlie the Canadian Shield, a vast belt of billion-year-old granite that alternately breaks the surface and dips below to saucer the treacherous muskeg bogs that swallowed countless carloads of fill while the railway was being built.

By evening you are skirting the northern shores of Lake Superior. Here the roadbed, clawed from the face of the rock, hugs the bank with so little room to spare that the left-hand windows of the train might as well be the portholes of a ship.

Morning of the third day dawns with the Canadian barely emerging from the forest, and from the province of Ontario. But within a few miles the trees thin to sparseness, and the prairies begin almost precisely at the Manitoba border.

If the North Woods seemed endless, the prairies will prove to be their equal. You may want to get off the train for a day or two in Winnipeg, a likable, casual yet cosmopolitan city that invariably surprises first-time visitors with its cultural resources, art and historical museums, and restaurants reflecting the city's polyglot ethnic mix.

Take a good look at the Winnipeg skyline as the Canadian pulls out of the station. It's the loftiest thing you'll see for the next 850 miles, until the glass towers of Calgary loom into view. In between lie the wheatfields of Manitoba, Saskatchewan, and eastern Alberta, punctuated only by Regina (Saskatchewan's capital), a handful of prairie towns, and the ubiquitous, colorful wooden grain elevators. Out here, the sky is far bigger than anything beneath it.

For all the prairie's subtle grandeur, it begins to wear out its welcome by the morning of the fourth day. That is when you arrive in Calgary, an oil city like its cousins Denver and Dallas to the south. As in those other boomtowns, Calgary has turned its petrochemical pretensions into extravagant downtown architecture. If you can, take a day off here just to visit the Glenbow Museum, Canada's finest institution devoted to western art, ethnology, and social history.

No sooner do you leave Calgary -- with the Canadian's windows scrubbed clean -- than the tracks follow the Bow River into the foothills of the Rockies.

For the next eight hours, the Canadian becomes the greatest train in the world, simply by virtue of the route painstakingly carved through the mountains by the engineers and heroic work crews of a hundred years ago. To them, the terrain was a barely surmountable challenge, but it wasn't long before the railroad management saw the potential for tourism and built the sumptuous resort hotels at Banff and Lake Louise.

To this day it doesn't seem quite right to approach the Banff Springs or the Ch^ateau Lake Louise except by train; one almost feels inclined to travel with a steamer trunk in the baggage car.

In winter, Banff and Lake Louise are where the skiers get off. It may seem unusual in this day and age to travel to a destination by long-distance train, but why not? Banff lies in the valley below Mt. Norquay and Sunshine Village, two top-notch areas. At Lake Louise there is Skiing Louise, Canada's largest ski complex, with 36 designated runs and eight lifts arrayed over three mountain faces. Shuttle buses connect the three areas with the Canadian Pacific and other hotels at Banff and Lake Louise.

You've come this far, so head for the coast -- or at least come back and finish the trip next summer, when the Vancouver World's Fair opens.

After cresting the Rockies and the adjacent Selkirk range, the Canadian begins its nighttime descent into the valleys of the turbulent Thompson and Fraser Rivers, through gorges charmingly named ``Jaws of Death'' and ``Hell's Gate,'' and the Fraser Canyon itself. By daybreak the Fraser is broad and flat, approaching its finish at Vancouver, as is the 3,045-mile run of the Canadian.

In the three-and-one-half days and four nights since leaving Montreal, its passengers will have seen that Canada, though far vaster than Gaul, is divided into three parts -- forest, prairies, and mountains. And they will have learned that those top-hatted Scots who met at Craigellachie just a century ago indeed had something to celebrate.

For more information, call Amtrak 1-800-USARAIL and ask for Via Rail Canada desk or call a travel agent.