ON A SUNNY summer day here, relaxed crowds stroll past shops in the Stroeget, the long pedestrian street, or sip beer at cheerful out-door restaurants in the Tivoli's oriental fantasy park. It is all very hygge; a quintessential demands quality pronounced so that the vowel's resemble "tuba."

I first heard of hygge at a political rally, of all places, in the provincial town Maribo. Workers and their wives sat at candle-lit tables in an arena covered with curtains and flowers, downing beers and singing Social Democratic songs.

"How coxy," I said

"That's Danish hygge." a Copenhagen colleague replied with a slightly superior air.

Since then, I discover hygge almost everywhere. It is in my hotel room, all redwood paneling and faded satin coverlets (also 40 watt bulbs which amy be hygge but are hell to read by).

There is hygge in the Graabroed-retorv, a cunningly irregular square where chaste, 18th Century facades look down at night on a throng delighted by free outdoor theater. A pair of mixed -up comics parody the hygge-less sex shows staged for tourists a half mile away.

There is even hugge at the Folketing, Denmark's parliament. Deputies slip away from debates to join journalists and friends for open faced sandwiches and beer in an inviting restaurant.

The word is all but indefinable and dictionaries here hardly try. It seems to be a special blend of snug comfort, case and unabashed delight in people, eating and drinking - something like the German gemnetlichkeit.

Other Scandinavians readily admit they do not have hygge. They blame their inhibitions on the isolated, rural communities from which most spring. A Swedish observer here says:

"Look at the map. The Danes have always been in touch with the Continent, with markets, trading with other people. We in the North are spread out; they are concentrated. All this makes for social intercourse and hygge oils it."

Clearly Danish life is pleasanter for hygge. The more disciplined and prudent Swedes and Norwegians seems power without it.

AT KONGELUND, a garden colony where 1,000 families own small plots and tiny summer homes, hygge is threatened by Copenhagen's bureacrats. The colony is a green lung for workers penned in high-rise apartments in the central city, but, like all these places, the land is owned by the municipality and Copenhagen wants Kongelund for a highway to the airport.

The Kongelunders have protested to city hall, arguing that gardens are more important than roads, that the highway can be placed somewhere else. This has not done nearly as much good as the fact that the city has run out of funds and so much postpone its plans. The Kongelunders have won a temperary reprieve, but they stay on only from year to year.

"I'm too old. I can't start a new place," said Oaage Frediksen, 67. For 20 years, he and his wife have been planting roses, black-eyed susans, panies and carnations in their 10-by-20-yard allotment.

"If this is taken away, I'll have nothing," Frederation said, and his neighbors spoke in much the same way.

THE GARDEN COLONY is one of Denmark's happiest social institutions. The first began 93 years ago, a troubled society's answer for people who had been pulled from farms to factories.

Copenhagen and other cities set aside vacant municipal land and lease it to workers for 25 or 50 years at nominal ground rents. Even today, a couple typically pay only $80 a year for 250 square yards.

Workers can reach their plots by bike, and they have tilled them with loving care. Every square foot is filled with glowing flowers, healthy vegetables or shining lawns. On each, the tenants have built garily painted houses, most of them little bigger than a doll's, just enough to sleep and feed two.

Some nature-starved city dwellers live in their colony houses five months a year, well into the cool weather.

"I'd be very sorry to start again," said Hans Nielsen, 60. "Here I have good friends. I planted the trees, the roses. I love this place."

If COPENHAGEN'S bureacrats have been stony-eyed over Kongelund, they have been far more tolerant of another haven, the dropout's uptopia, Christinia.

This astonishing place, a 15-minute bike ride from the center of Copenhagen, consists of 25 wooded acres and sylvan canal. It contains nearly 200 solid brick barracks and other buildings left behind by the military.

Six years ago, the students, commune dewellers and others who lived in a nearby slum saw that this vast estate had been abandoned and was lying unused. They poured in, set up house, and established their own "free city." Bemused authorities feared a confrontation and were reluctant to push them out by force.

TODAY, THE SQUATTERS number about a thousand, set up their own anarchist non-government ("no cars, no hard drugs, no violence"). They live on jobless benefits, student grants and the furniture, woven rugs, pottery and bicycle trailers they make and sell to tourists.

Christiania's resident philosopher is Per Lovetand, a successful professor of architecture who dropped out to live with a woman, Vibeke, and their daughter in a remodeled munitions laboratory.

"We're building up new norms and values," he asserts."Social values count more than materialistic values. It's essential to have a good time together, not produce, produce and overproduce. Spontaneity, not planning. Learn from practice to gain a higher understanding."

Copenhagen and the Defense Ministry would like to reclaim Christiania, and a court has ruled that they can, legally. But the judge also said that Christiania is a valuable institution, saving society the expense, among other things, of caring for what had been some hopeless drug addicts.

A higher court is due to settle Christiania's fate this fall. The fact that it has survived so long is a Striking measure of Denmark's relaxed tolerance.