Prague. It's the first city on our tour of eastern Europe where we literally find them dancing in the streets.

It's not the first time. The history books tell us there was general rejoicing during the Hussite rebellion of 1419, when an angry mob led by Jan Zelivsky stormed the town hall and tossed the consuls out the window. (Hus himself, a Protestant reformer, had been burned at the stake four years earlier.)There were further defenestrations in 1618, when three Catholic councilors were hurled into the moat of Prague Castle, helping trigger the 30 Years' War. Then two centuries later, with the country still under Austrian rule, there were the celebrations in support of the revolutions of 1848, culminating in the convening of the first Slavic Congress. But that ended with fighting in the streets and, ultimately, surrender.

Indeed, the Hapsburgs ruled Prague until 1918 and the end of World War I. That year the city became the capital of thenewly created Czechoslovakian state and, amid much rejoicing, Tomas Masaryk was welcomed home from exile as president of the new republic.

More rejoicing came in 1945, with the defeat of the German occupation force at the end of World War II. The liberating Red Army came to symbolize something else, however, with the Stalinist repressions of the late '40s and early '50s. Finally the "Prague Spring" of 1968, a liberal reform movement under Communist Party leader Alexander Dubcek, was brought to its knees by Soviet tanks rolling into the city, crushing further hopes for Czech independence for another two decades.

Then in 1989 the unthinkable happened. Playwright Vaclav Havel, arrested earlier that year for having taken part in the protests marking the 20th anniversary of the Soviet invasion, went from being sentenced to nine months in prison to being elected president - the first non-Communist to hold that office in more than 40 years. Within days he proclaimed the first free elections since the Communist takeover of 1948. The result was that, the following June, 96 percent of Czechoslovakia's 11.2 million eligible voters turned out to cast their ballots. (Remarkably enough, the Communists still came in second.)

Two months after those elections, one can still see posters bearing Havel's likeness hanging from the walls, many inscribed with slogans celebrating his victory. Indeed the torch now seems to have been passed to the young, who crowd the Old Town Square chanting songs of triumph. Have we stumbled by chance on a political rally? No, I am told. The euphoria simply hasn't died down.

But we do seem to have come at a propitious time. Having parked our car on a side street - about the only parking available on a Saturday - we have made our way to the square just as crowds are gathering to greet the striking of the noon hour on the astronomical clock on the southern face of the Old Town Hall.

The tower itself dates from 1364, the clock in its earliest form from 1410. The central portion depicts the movement of the sun and the moon through the zodiac. However, it is the upper portion that is the real attraction, as every hour on the hour the figure of death rings the knell and upends an hourglass as the 12 apostles march past and a cock flaps its wings and crows.

Does this little panoply, and the shouts it evokes, now suggest the death knell of Communist rule? It's hard to know, but it seems to me significant that the other big attraction on the square, opposite the clock, is what I take to be the Czech version of the East German Lada - generally thought to be the ugliest, least efficient car in all of eastern Europe - mounted in effigy, as it were, and bronzed atop four cumbersome-looking human legs.

Already, we are told, the Red Army has begun its pullout, to be completed next June. Still, Russian is the second language on the maps and guidebooks we are able to buy just off the square and, we find, English is no help - with our virtually nonexistent Czech, it takes German to get them.

German is also the language we are approached in by a shifty-eyed young man with a camera bag wanting to know if we are interested in changing money. He is not the first. Barely a mile past the border this morning, we were flagged down by the first in a long line of black-marketers in currency, cheerfully waving Czech money at us from the roadside. All offer better than the official rate - anywhere from 16 to 18 crowns, as opposed to 15.6, for one German mark - but we have been warned about this kind of thing. Not only is there the risk of obtaining counterfeit money (would you know the difference?) but, on leaving the country, all visitors are required to show any money they have, together with a receipt from a bank or currency exchange.

Otherwise crossing the border is simplicity itself. Earlier in the year we were told we would need not only our passports but a visa to enter Czechoslovakia. Then, a week before we left, that had been relaxed to the purchase of a visa at the border. By the time we arrived, driving southeast from Dresden, all the guards asked to see was our passports - we didn't even have to get out of the car.

Still, it is the old Prague that fascinates me, as it did the poets, artists and musicians of the 19th century. And there is no better place to begin that trip into the past than Old Town Square.

In fact all streets seem to lead to it, whether past the baroque facade of St. Nicholas Church on the north, the Old Town Hall on the south or, on the east, the Bohemian-gothic spires of the Tyn Church, until 1621 the main church of the Hussites. Within the last lie the remains of the 16th-century Danish astronomer Tycho Brahe, while in a more contemporary vein we discover that the house next to the Nicholas Church is the birthplace of the writer Franz Kafka.

At the center of the square, however, stands an impressive memorial to the reformer Jan Hus. Erected in 1915 on the 500th anniversary of his death, it has become a rallying point for Czech nationalists ever since. Indeed the legend still persists, especially as embodied by the composer Bedrich Smetana in his symphonic cycle "Ma Vlast" ("My Country"), that in its hour of peril the Hussite warriors who sleep within Blanik Hill, to the south, will come forth to rescue their homeland.

Actually the original legend is that it is the Czech patron saint Wenceslas - yes, "Good King Wenceslas" - who sleeps within Blanik with his knights. And Wenceslas likewise has his memorial in Prague, a celebrated equestrian statue overlooking the square that bears his name, likewise a gathering place for marchers and demonstrators over the years.

The best-known of the six tone-poems that make up "Ma Vlast" is, however, "Vltava" - "The Moldau" - in celebration of the mighty river that flows north through the city. Two hundred and seventy miles long, it rises from two headstreams, the Tepla Vltava and the Studena Vltava, ultimately linking Prague with the Elbe and thereby the German port of Hamburg on the North Sea. At one time, we are told, winter fairs were held on its frozen surface, but that was before the dams were built that now control its flow.

For 500 years the only link between the two river banks was the Charles Bridge, named for the 14th-century Emperor Charles IV. Probably the last of three bridges to have been erected on this site, it has withstood flooding, temperature extremes and even 20th-century automobile traffic until it was declared a pedestrian walkway some years ago.

Between it and the Old Town Square we encounter our first signs of home - a poster announcing a Joan Baez concert and an "American Hospitality Center" flying the stars and stripes and dispensing Classic Coke for travel-weary Yanks. But it is the bridge that draws us onward, past the taverns and restaurants out of which pour an astonishing amount of lunchtime singing and shouting. Even indoors, Prague appears to be a lively town.

Between the two gothic towers at either end, the bridge is also a lively place, filled with tourists and trinket vendors - even, I notice out of the corner of my eye, our friend with the camera bag. We stop for some juice and a pretzel, both very cheap compared with German or American prices.

We also stop to admire the baroque statuary lining the bridge, 30 of them, by my count, ranging from that of St. John Nepomuk, erected in 1683, to the knight Bruncvik, whose sword is said to be walled up in the bridge to be retrieved in Czechoslovakia's darkest hour.

The bridge was built at Charles' behest by the architect Peter Parler, who also supervised the building of St. Vitus's Cathedral. After his death, his sons continued the work on the latter until it was interrupted in the first half of the 15th century by the Hussite wars. In fact the cathedral was not fully completed until 1929, the plans having been taken up by a Czech patriotic organization.

Today it is still the dominant feature of the city's landscape, capturing the eye as soon as one crosses the Vltava from the north. Towering above the fortifications of Prague Castle, of which it is part, its lofty spires somehow symbolize the indomitable Czech spirit. And, as we make our way up the steep cobblestone street that leads to the castle, I realize it is going to take a certain amount of indomitablity on our part to see it.

More statues greet us outside the main entrance to the castle, imposing copies of the "Battling Titans" of Ignatius Paltzer the Elder. Happily we are just in time for the changing of the guard, and outside the cathedral, in the inner courtyard, a group of folk dancers and musicians.

But it is the towering west portal of St. Vitus's that takes our breath away, as it rises abruptly above our heads as we enter the inner court. A magnificent example of gothic architecture, its towers are decorated with the statues of 14 saints. And its interior is no less impressive, its vaulted ceiling seemingly rising to the sky itself above the heavy silver and gold altars and ornately fashioned stained-glass windows.

Inside the cathedral one finds the chapel of St. Wenceslas, built on the site of the 10th-century Roman rotunda in which he was interred. Adorned with gold and semi-precious stones, its walls depict the passion of Christ and the saint's history. Behind seven locks, in the treasure chamber above, are kept the Bohemian crown jewels. Another staircase leads down to the royal crypt, containing among other things the tomb of Charles IV, his four wives and his children.

Smetana, however, and his contemporary Dvorak are buried in a more fitting place, the cemetery of the Vysehrad - "The High Castle" - the seat of the ancient kings of Bohemia. Indeed the former chose to begin his "Ma Vlast" with a bardic evocation of this ancient shrine.

Here, according to legend, is where the Princess Libussa had her great vision of Prague's future glory under her and her husband's descendants, the Premyslids, who ruled until the 14th century. As recreated by the artists of a later day, the couple were supposed to have lived in a magnificent palace, since fallen into ruins.

Rising from the right bank of the Vltava, greeting the river on its approach to the city, its ruins can still be seen, but again it takes a climb. The oldest building on the Vysehrad is St. Martin's Rotunda, dating from the 11th century, one of the oldest churches in Czechoslovakia. More imposing is the Church of St. Peter and St. Paul, erected in the late 1880s, whose neo-gothic spires rise high above the rock and the highway construction at its feet.

These days when "Ma Vlast" is performed, it is usually closer to the heart of the city, such as at Prague Castle or the hall that today bears Smetana's name. Last year, however, on the occasion of the city's "liberation," it actually got an outdoor performance under conductor Rafael Kubelik, returning to his homeland after more than 40 years in voluntary exile.

That seems appropriate, I think, as I look down on Smetana's beloved Vltava from the hill that holds not only his body but his hope of his country's future, not to mention Libussa's. (Earlier he had also written an opera about her, a performance of which opened the National Theater in 1881.) Because the music of Czechoslovakia doesn't sound from its buildings. It sounds from its trees, its mountains, its rivers and its wheatfields. And most of all from its people, whose ancestors are supposed to pour forth from those mountains when their country stands in need of deliverance.

On the other hand, maybe they already have.