Surrounded by a succession of Alpine giants, this isolated rail station is so high that it actually looks down on ski routes. Perhaps the most remarkable thing is that you can get here on a regular, scheduled Swiss train that runs several times every day of the year, no matter the weather, and there's no extra charge for getting you to the roof of Europe.

The Glacier Express - which celebrates its 75th anniversary this year - is one of the world's great and most remarkable railway journeys, ferrying tourists in panoramic carriages through the heart of the Alps, from the world-famous resort of St Moritz to the foot of the needle-sharp Matterhorn - the country's national symbol.

"The main thing is the change in nature in total,'' says Helmut Biner, spokesman for the Matterhorn Gotthard Bahn, which runs the western section of the route. "It is quite impressive because it's in the heart of the Alps and with all these rivers and valleys to cross.''

Tagged "the slowest express train in the world,'' the Glacier Express takes passengers at an average speed of 30 kph through the mountainous canton (state) of Graubuenden before climbing up the Rhine Valley to cross the Oberalp Pass, at 2,033 meters the highest point on the route at a nexus of ski lifts.

It then descends with the River Rhone before turning into a side valley to reach the world-famous resort of Zermatt, at the foot of the Matterhorn's pyramid. The whole journey takes some seven hours, crossing 291 bridges and rumbling through 91 tunnels.

The route is a celebration of Swiss engineering, from breathtaking viaducts crossing rushing mountains streams, to switchback rail lines which sometimes even go in full circles to spiral up or down the steepest slopes.

"We did a survey last year, and 81 percent (of passengers) said they would tell friends to take the Glacier Express,'' says Biner. "That's a good figure.''

The number of people traveling on the scenic train rose rapidly through the 1980s and is now fairly constant at about 250,000 a year, Biner explains.

"Often it's better to make reservations, to be sure to get space,'' he adds, noting that the Edwardian-era restaurant car is a very popular feature. "The nature stays more or less the same, but we try to give more comfort as well.''

For those of you who want to escape the hordes of camera-clicking tourists, you can also follow the spectacular route on regular trains and plan your own stops.

Many of the regular trains are almost empty and have the same panoramic windows and dining facilities. This option also gives travelers the chance to spend some time in the charming old city of Chur along the route, and in any number of small mountain villages, where often the only other people you encounter are the Swiss themselves. Regular trains won't charge extra if you hop on and off.

On the Glacier Express, it costs more to stop along the way, but with reservations, passengers are guaranteed the panoramic carriages and access to the dining car.

From St Moritz, the Glacier Express route cuts through a tunnel into the high Albula valley, which it then descends in a series of breathtaking spirals. At times, it barely seems possible that your train has just descended from tracks now visible far above.

Remote places like Berguen and Tiefencastel offer a chance to break the journey and get away from it all, perhaps fitting in some hiking or sledding. Just before Tiefencastel, the train rumbles out of a tunnel and over the soaring Landwasser viaduct.

About 90 minutes from St Moritz, the train descends to the Rhine Valley, bringing travelers into Chur, the largest town on the route, surrounded by steep-sided mountains and supposedly offering the best shopping between Milan and Zurich as well as a variety of accommodations and dining.

Above the cobbled streets of Chur's old town is an onion-domed cathedral. Vineyards and forests cluster up the hillsides, offering rural walks just five minutes from the center of town.

Leaving this pretty town, the Glacier Express then climbs along the rugged Rhine gorge, chugging along next to the young river, which burbles between two sheer rock faces. Halfway along the Upper Rhine Valley, the train reaches the small town of Disentis - also known as Muster in the local mountain language of Romansch - with its monumental white Benedictine abbey, with exuberant and intricate interior decorations.

Then starts the long haul up to the Oberalp, climbing through snow fields as skiers jump on and off, ferrying up to the top of the ski runs. In the picturesque village of Andermatt, situated at the foot of four great Alpine passes, you can stop for refreshments and stretch your legs before the long descent through a region known as the Goms, which has fine cross-country skiing.

The final stretch is possibly the most dramatic, as the train uses cogs to climb the steep Matter Vispa valley, anticipation mounting as passengers await their first view of the Matterhorn at every turn.

``It's one of the highlights, especially, the Matterhorn at the start or the end of the trip,'' Biner says.

But travelers have to wait. Their first view of the majestic mountain comes only after stepping outside Zermatt's train station.