By DILIP GANGULY, Associated Press Writer

JHAPA, Nepal, Jan. 13 (AP) -- Not far from Mount Everest, 100,000 refugees live in snake- and leech-infested camps as exiles from the Land of the Thunder Dragon.

Six years ago, they were driven out of Bhutan, a tiny, unspoiled land of green mountains that travel books describe as the last Shangri-la.

On Sunday, 150 of them will begin a 23-day, 250-mile march from their camps in Nepal, across India and up the Himalaya Mountains to Bhutan's capital, Thimphu, where they will ask King Jigme Wangchuk to let them return.

It is doubtful they will finish, and even if they do, the king is unlikely to grant their request. The refugees are caught in a battle over whether there is room for diversity in Bhutan.

The refugees are ethnic Nepalese whose families have immigrated to Bhutan to find work and fields to farm. They are mostly Hindu, and they wear different clothes and speak a different language from the Drukpa majority.

When Bhutan tried to force them to adopt the ways of the majority, they resisted and were driven out, fleeing to eastern Nepal.

Dali Ram Kharel, 22, was a student in Bhutan in 1992 when his father sent a message to his dormitory saying his family was being forced out of the country.

"I was left alone there, so I decided to leave," he said.

Nepal, one of the world's poorest countries, wants the refugees to leave.

Bhutan, calling them agitators who want to overthrow the monarchy, doesn't want them back. So for now the refugees are stuck in eight isolated U.N.-run camps amid mustard fields and mango groves.

A trip by road from the Nepalese capital, Kathmandu, takes three days. The area's small airstrip is flooded for four months of the year.

Snakes slither across the roads. U.N. workers are under orders to use mosquito nets because the abundant pests spread malaria and encephalitis.

"It is terrible living here," said Arun Sala-Ngarm, the chief representative of the U.N. refugee agency, who once found a cobra in his office.

The marchers hope to make Bhutan reconsider their exile. But they aren't likely to get far. Bhutan has asked India to stop them at the border, and India, which has close defense ties with Thimphu, will probably agree.

The march nonetheless will draw attention to the plight of the refugees, which six rounds of talks between Bhutan and Nepal have failed to resolve.

The Drukpas are Buddhists who came from Tibet hundreds of years ago to what they call Druk-Yul -- "Land of the Thunder Dragon." They see the Nepalese -- recent arrivals in comparison -- as a threat to their domination of the country.

In 1988, Bhutan began a "one nation, one people" campaign, decreeing that anyone who could not trace residency back to 1958 was no longer a citizen.

All citizens were required to learn the Bhutanese language, Dzongkha, and were told about the benefits of following Buddhism.

Men were ordered to wear a Kho, a wraparound tunic, while women were to wear a Kira, an ankle-length robe with a jacket. The heavy woolen mountain clothes are unsuitable for the semitropical weather of the south where the Nepalese live.

The government also tried to promote marriages between Bhutanese and Nepalese, offering $285 to such couples willing to tie the knot.

The ethnic Nepalese, feeling that their culture was being destroyed, began an anti-government uprising, trying to topple the king and replace him with a democratic government.

There were murders and attacks on schools and government offices. In September 1990, army troops opened fire on a demonstration, killing three people.

The refugees do not hesitate to say that they will resume their campaign if they are allowed to return.

"We will certainly usher in democracy in Bhutan," said Laxmi Narayan, 55, a former clerk. Four years ago, he fled Bhutan with his wife and four children after he was jailed for three days.

"On the third day, they told me they will set me free if I leave Bhutan," he said. "And I did. I had no option."