Yugoslavia's Plitvice -- a well-kept secret. National park's awesome beauty ranks with Norway's fjords

To most people, ``Going to Europe'' means visiting Great Britain and France, with perhaps another Western European country thrown in for good measure. Yet there is much more to Europe. Consider Yugoslavia: Not only does it equal any other European country in its offerings for tourists, it also surpasses most. And I'm not speaking just of the Dalmatia coast, of Split, of romantic moonlit nights, or ancient, atmospheric Dubrovnik, but rather of the little-known natural wonders at Plitvice.

After repeated visits, I rank Plitvice with the Norwegian fjord country as the loveliest spots on earth. Of course, the majestic grandeur of the fjords can best be experienced from a ship. In Plitvice, however, you can walk the winding paths between countless lakes and waterfalls. The peace is overwhelming, the air pure, the waters pristine.

Getting to Plitvice isn't difficult. By flying to Zagreb, you can reach Plitvice by bus or car in an hour and a half. My favorite itinerary, though, is to travel by car from Trieste, by way of the Yugoslavian city of Ljubljana. The drive has much to offer.

Enroute, we like to stop at the Postojna Caves, reputedly the world's third largest. A small railroad offers visitors spectacular views.

Not long after the caves, one comes upon the ancient city of Ljubljana, a photographer's paradise with its mellowed yellow buildings and churches, colorful flower and vegetable market, and modern section spreading out toward hills in the distance.

Ljubljana, a university city of about 250,000 people, was founded by the Romans 2,000 years ago on the river Ljubljanica. The atmosphere is reminiscent of Prague or Vienna, on a smaller scale. The city's National Museum and National Gallery and the university library's collection of rare and ancient books are likely to be of interest to visitors.

But the main attraction in Ljubljana is its musical life. The city's permanent opera company is outstanding. And, during the summer, the city's six theaters mount the Ljubljana Festival, with guest performers from around the world. The Ljubljana Symphony, which sometimes visits the United States, also has a reputation for excellence.

There are some good hotels in Ljubljana. Among the newer ones, the Holiday Inn offers a double room with bath or shower for about $80 a day, and the Lev (Lion), which I prefer, a double with bath at about $40. Among the older hotels, the Slon (Elephant), priced at about $40 a day for double with bath, is a popular one. (An annual listing of hotels and prices is available from the Yugoslav Tourist Office -- see address below.)

After leaving Ljubljana, the motorist encounters only the smaller towns on the road to Plitvice. The countryside gives no hint of the wonders to come. One moves suddenly from a region of relatively sparce vegetation to a wonderland of mountains and streams, lakes and waterfalls, tarns and pools.

The 75 square miles of lakes and trails at Plitvice were designated a national park in 1949 and placed on UNESCO's list of the world's natural heritage spots. Sixteen lakes on various levels spill into each other by way of waterfalls large and small, high and low, wide and narrow. The waters cascade from rocks, from around tree trunks, from in between tall grasses.

Natural dams formed by the deposits of centuries separate the 16 lakes. Algae, moss, and soft sandy stone are still being deposited, and thus are imperceptibly changing the channels and curtains of water. The lakes are clear enough for one to see ancient, submerged trees and fish swimming around a sunken boat. The water is clean enough to drink.

Although one is apt to encounter visitors here of many nationalities -- Yugoslavs, Belgians, Norwegians, Indians, Brazilians, Japanese, and Balinese during our most recent visit -- the wide, well-marked trails are far from crowded. Lookout points and terraces offer resting spots and incredible views. The highest waterfall, which drops some 200 feet, provides a favorite setting for wedding ceremonies. Couples come from many countries to get married in this unusual spot.

One word of advice: Try to allow more than one day for Plitvice. It is frustrating to see only part of this exquisite place. Two days give you a chance to savor it. And, if you're looking for a quiet resort, you might want to stay even longer.

There are no movie theaters or nightclubs. There is little social life or entertainment beyond an occasional hotel band. There are two Class A hotels, both more or less Scandinavian in style and open year-round. The Hotel Plitvice, with 150 rooms, costs between $32 and $56 for a double with bath or shower per day. Full board runs an additional $30 to $40 per person. The newer Hotel Jezero (Lake) has 480 rooms, and its prices are about 5 to 10 percent higher. There are other hotels as well, and most of them have restuarants. Practical information

Good travel literature on Yugoslavia is available in English. Send a post card (better than letter) to the Yugoslav National Tourist Office, 630 Fifth Avenue, New York, N.Y. 10111. Be sure to ask for a map as well.

If you are interested in visiting the site of the 1984 winter Olympics, Sarajevo is inland on a winding road from the coast, roughly between Dubrovnik and Split.

Vera Laska is a frequent visitor to Yugoslavia; she teaches history at Regis College in Weston, Mass.