PEOPLE OFTEN ask why you return to Zermatt year after year, and usually you tell them about the Piste Nationale, that seven-mile plunge down the steep north face of the Rothorn, across glaciers and pastures and through the tree-line to the village which, even as you ski in the bright afternoon sun, is already shrouded in dusk, lights twinkling and chimneys smoking.

You explain how the mountains, cold and white, enclose the valley, and how the snow blows off the Matterhorn in an angry cloud. When feeling particularly expansive, you might mention how the snow to a depth of six feet blankets the hotels and cow barns, and how good it feels at night to sit with a drink by the fire in a dark old inn, listening the the laughter of a dozen languages and the distant crack of avalanches rumbling down the now invisible mountains.

You tell those of a more practical (albeit romantic) turn of mind that cars have been banned from the village -- no one seems to mind, as can walk anywhere in 15 minutes -- and that horse-drawn sleighs, piled high with blankets and sometimes cheeses round as barrel kegs, await travelers at the station, the last stop of a stomach-tightening 1 1/2-hour trip from Brig on the 90-year-old cog railroad.

And after talking about these things you want to go back. So you do. Many European resorts lay claim to better skiing, more energetic nightlife, a richer or more littery clientele, but none combines the elements of classic alpine skiing better than Zermatt, this perhaps most perfect Swiss resort. Skiing

Zermatt is really three areas in one, each offering a wide range of novice to expert trails and boasting one of the highest verticle drops in Europe. An ample variety of cable cars, cog wheel trains and ski lifts keep lift lines to a minimum. This, combined with the length of most runs, makes for some very intense skiing and by the end of the day you are usually beat.

The Sunnegga/Rothorn slopes tend to have the best intermediate and advanced runs, in part because their southern exposure offers softer snow and protection from the wind. This makes them more crowded, but last year Zermatt introduced an underground subway that whisks skiers from the village to the upper lifts and reduced the formerly severe waiting lines to almost nothing.

The large novice and intermediate area, Gornergrat, is served by a cog wheel train that winds several miles along sheer cliffs and over waterfalls to the hotels, well-groomed hiking trails and pistes between Sunnegga and Schwarzsee, the more expert area directly beneath the Matterhorn. Schwartzsee's cable cars give an unparalleled view of the Matterhorn and its acolyte peaks. The winds are colder and harsher here, as befits the steep and narrow trails and powder.

Most of Zermatt's slopes are above the tree-line, and straying from the piste can be dangerous. Slopes marked with a black sign are most difficult and for top-flight skiers only. Red slopes are less difficult but still advanced. Blue are easier, and green are for beginners. Pistes marked Gesperrt are forbidden; those marked Gessschlossen are closed and skiers try them at their own risk.

A surprising number of skiers do tempt the closed trails and deep snows far off the piste, usually without mishap. But at least once a month the guides rescue some intrepid soul who has wandered into the snowy beyond and started his own small avalanche.

If you have more than four days in Zermatt, spend one in Cervinia on the Italian side of the Matterhorn. The Theodul Pass bridging the two countries is steep, and the way to ski into Cervinia is to dive in -- a long, clean schuss onto the run-out several hundred yards below. As with Sunnegga, Cervinia's southern exposure means that slopes which in Zermatt might be too cold or icy to ski are warm and soft in Italy. After the long run down you might treat yourself to lunch on the terrace of a boisterous Italian restaurant. And take your passport; sometimes the Swiss border guard won't let you return without it.

Apres Ski

Unlike Gstaad or St. Moritz, where skiing runs a distant second to jewelry, dining and disco as a sport d'hiver, Zermatt takes its alpining seriously. People come to Zermatt for one thing only -- the skiing and climbing. All else is secondary.

That said, however, Zermatt is far from dead at night. The Bahnhofstrasse, the narrow street running through the center of town, is virtually lined with cafes, bistros, hotels, discos and other paraphernalia of apre's ski. In choosing among them, you should know Zermatt's rhythms.

In mid-afternoon when skiers begin to come down from the slopes, the cognoscente first go to the tea rooms -- a uniquely Swiss institution which is as different from the American coffee house as layer cake is from Napoleons. Zermatt has dozens of these quaint and civilized small places, usually located above restaurants or shops and existing only as comestible way-stations, places to read the paper after breakfast or relax after skiing. If the mornings are given over to quiet and contemplation, the afternoons strike the opposing chord. In the tea rooms people meet up with lost companions, make trysts for the evenings, eye one another and talk a blue streak. The medium is coffee and pastries, a sort of starter menu for the move to heavier and more liquid fare as evening becomes night and, many happy hours later, dawn.

Between 5 and 6 o'clock the town moves into the bars. Some are extremely posh, as in the famous Mont Cervin Hotel, others more basic. Elsie's, a 300-year-old chalet on the main square in front of the church, compresses some 50 people into its warm confines every evening until 9. If you don't like to sing, or can't stand others singing, don't go.

A leisurely dinner of raclettes, a large pool of fresh melted cheese surrounding a small pile of baked potatoes, gives a pretty good base from which to start the rest of the evening. For piano bars, fireside lounging or jazz, you go to the hotels. The younger crowd, or those bent on burning the candle at both ends, heads into the Bahnhofstrasse and usually doesn't go home until 2 or 3.

By this time the snowy street melted earlier by the milling crowds is empty and frozen smooth as glass. Salting seems foreign to the 21 families that own and run the town, and so in the wee hours it's not unusual to see a human bobsled or two whizzing down Bahnhofstrasse and arcing off into a snowbank or creek. All told, it's far better to close the evening by falling supine into the nearest sleigh, where you can lie deep in the blankets watching the stars as the faithful horse and driver clip-clop you home to bed.

Hotels

Zermatt like the rest of Switzerland is more up and down than sideways, and on every flat surface is a hotel or a shepherd's hut converted into a hotel. Zermatt's newer hotels all seem to be cut from the same pattern, great brown gingerbread places hung over with balconies and high-pitched roofs. The older places bear more Italian and French than Swiss influence, and hotels like the five-star Monte Rosa are large, pastel-colored palazzos with rows of Renaissance windows and grand, substantial entryways. They are as expensive as they are elegant, with daily rates ranging from $25 to $90 a day.

The town council boasts that half the rooms in Zermatt look out upon the Matterhorn, which may or may not be true or even desirable, depending on your taste for alpine views. Overkill is considered no sin in Zermatt. If your room does happen to look upon the Matterhorn, you might also find a framed Matterhorn above your bed and a poster Matterhorn in the bath. If so, call down and ask for more.

If you are willing to settle for vistas other than the Matterhorn (which could mean anything from other mountains to the cook's bathroom in the adjoining hotel), Zermatt offers a variety of economical, high-quality lodging. The two-star Testa Grigia and three-star Gornergrat, charging between $25 and $35 a day, with breakfast, are ideal budget-class hotels, centrally located.

The Welschen, an older chalet, accommodates a smaller number of guests in a wooded park just outside town. The tariff, ranging from $13 to $34 a day, guarantees unobstructed views not only of the Matterhorn, but every other peak you could wish to see.

The People

Different nationalities come to Zermatt in waves, each as predictable as the migrations of wild birds, each transforming the town. In January, when the Germans congregate, you would think that you had turned left rather than right in Geneva and ended up in Munich. The singing at Elsies is then in German and the barmaids who last week all spoke French now rattle off their Gruss Gotts like native Dusseldorfers.

For reasons known only to themselves, the French favor December and February, the English late fall and early spring, and the Americans just about any time at all. The Italians pop over the mountains as regularly as bubbles in Folonari.

Almost everyone in Zermatt speaks some brand of English -- most willing to use it at the slightest provocation. Meeting people thus becomes remarkably easy, which is good to know if you are traveling alone. You'll be sitting in Elsie's nursing a beer when the male half of the Italian couple sitting across from you leans over and says: "How-dee. We saw you ski upstairs and think to say you drive very well." That means they saw you on the slopes and thought you were hot stuff. Presto -- tonight you drink with friends, tomorrow you don't ski alone.

When, as it must, struggling over the language barrier becomes too tough, the best place to go is the bar with no name. Any hotelier will give you directions, and they usually go like this: "Take the alley past the church and go over the bridge. Go straight for 50 meters, take your second right. Go 20 meters, climb over the snowbank on the left and open the door facing you."

The door is unmarked, but go in and you're greeted with a burst of noise and warmth . . . all in English. The bar is frequented by Americans, Brits and New Zealanders of all ages, all looking for one another's company. Beer costs 50 cents, a third as much as elsewhere, and once caught you will probably wind up there every night.

A note to the budding glitterati: the Aga Khan, Adnan Khashoggi, representatives of the Van Cleef, Gerard, Boucheron and Winston families, rich arabs and Greek shipping magnates tend to stay away from Zermatt. Perhaps it's the number of families who go there or the absence of exclusive clubs. In any case, the only breath of the international haut monde circulating last season involved the efforts of an overly zealous jeweler to sell his wares to an English baronet. The dealer took some photos of the young baronet whipping his girl friend, whom he had tied to a post. When the dealer showed him the negatives and hinted that an exchange of services might be made, the baronet congratulated the dealer on his photographic talents and advised him which pictures he would like to have developed and enlarged. The furious salesman burned the negatives and left town, never to return.

For Non-Skiers

Europeans eagerly go to places known as ski resorts when they have no intention of skiing, an urge Americans are only beginning to understand. Far from being so drearily snowclad that only skiers could care, Zermatt in winter is as rich for non-skiers as for skiers. In the afternoon the town is filled with people who prefer (not insensibly) hiking, skating, swimming, shopping, eating, romancing and talking with friends to strapping boards on their feet and hurtling down a mountain.

The eating part of all this should not be approached casually; lunch is Zermatt's second passion. While few of us would set off for the alps with meals in mind, many Europeans do. The reason is that while our ski towns are generally bitter and cold, the alps are remarkably mild. One of Zermatt's great pleasures is to sit in the sun on the terraces of the many inns and hotels spread across the slopes and admire the view, eat and drink the fine Swiss wine.

The smaller inns down among the trees at the edge of the pistes and hiking trails near town are particularly charming, quiet and secluded. Sitting there you might fall into conversation with someone nearby and ask how long she will be staying in Zermatt. "Until my master calls," she might answer.

"Your husband?" you inquire, puzzled.

"No. My Master, Maharishi Yoga." She says she is in Zermatt because she likes skiing "where heaven rings," and then turns to gaze outside at the snow sifting gently and silently through the pines.

She is content to do nothing else, and in Zermatt that seems perfectly appropriate.