THIMPU, BHUTAN -- Its citizens seldom write letters and there's not a single stamp collector in the country, but Bhutan -- one of the world's most isolated kingdoms -- has made an international name for itself issuing exotic postage stamps.

The Himalayan nation built its first paved road, switched on its first light bulb and opened its first post office only 32 years ago, yet it will print the world's first three-dimensional postage stamp.

Most letters and packages are still delivered by dagger-toting foot couriers who brave wild animals, leeches, dense jungles and bare windswept ridges to reach their customers, but this year Bhutan will issue a futuristic holographic stamp commemorating the first American moon landing 25 years ago.

"Stamps have popularized our country," said Jigme Tenzin, controller of philately for the country's Office of Posts, Telegraphs and Civilian Wireless.

More important, according to some government officials, the sale of stamps to foreign collectors has become one of this tiny country's biggest moneymaking enterprises. In a nation that depends on foreign aid for about half its budget and has only a handful of exports, the postal service pulls in up to $485,000 a year from foreign philatelists.

International collectors are so important to postal profits here that the postal service sends only its leftover stamps to district post offices for sale to the general public, according to Tenzin. The main post office here in the capital, for example, recently was selling a colorful nine-year-old stamp celebrating a 1985 South Asian regional conference for use on postcards mailed overseas.

Not that most Bhutanese can relate to many of the stamps issued by their postal service, such as a stamp showing Donald Duck watching television on the back of a yak in a kingdom where there is no television station and where the king has banned satellite dishes. Or a delicate stamp of the USS Constitution in a landlocked nation that has no navy. Or a three-dimensional stamp of an American Apollo astronaut driving a moon rover in a country where the majority of people have never been in an automobile.

"Donald Duck was not very popular here in Bhutan," admitted Tenzin. "But he was very popular in the U.S."

In addition to the three-dimensional stamps showing astronauts floating in outer space, exotic butterflies flapping over flowers and fish swimming through azure waters, Bhutan has produced exquisite silk stamps and has commemorated the development of the world's steel industry with a set of 12 stamps printed on hair-thin 0.001-inch steel foil, the first such stamps ever produced. Among collectors, Bhutan's stamps of famous paintings, including Claude Monet's "The Corn Poppies," which was reproduced on paper that feels like an oil painting on canvas, are among the most prized.

In recent years, international philatelic agents have been influential in persuading small nations such as Bhutan that there are big profits in printing "theme" stamps popular with overseas collectors. Bhutan, like many other small countries, uses such organizations as the Intergovernmental Philatelic Corp. in New York to design and produce many of its stamps.

"We don't have a printing press," said Tenzin, who said Bhutanese postage stamps are also printed in Singapore, Japan and Britain.

The Bhutanese postal service has discovered that stamps commemorating the Buddhist lunar year -- currently the Year of the Dog -- are among its most popular productions, particularly among Chinese and Japanese collectors. Wildlife enthusiasts as well as stamp collectors go for stamps depicting endangered animals and birds -- such as the golden langur, a yellow-furred member of the monkey family believed to be found only in Bhutan. The rare black-necked crane, which winters in central Bhutan, has starred on several stamps over the years.

In the past year or so, however, even international collectors have begun turning away from themes celebrating anniversaries of world events, birthdays of world leaders and construction of global landmarks and moving toward more indigenous depictions. As go the whims of stamp collectors, so goes the production of Bhutanese stamps.

Stamps publicizing the country's rich heritage are among its most extravagant. An entire series was devoted to the Yeti, better known to Westerners as the Abominable Snowman, an important component of local religion and folklore.

But none of this has inspired the Bhutanese, with an adult literacy rate of about 15 percent, to do more mailing. While the U.S. postal system moves an average of about two pieces of mail for every American resident each day, the Bhutan post office delivers an average of 2.5 items for each citizen in an entire year.

"Our postage sales here are limited," said Tenzin. "People don't write many letters, and there are no collectors in Bhutan."

Even so, thanks to the foreign market, Bhutan -- a country of about 600,000 residents -- will print 200,000 copies of its hologram moon-landing stamps for release in July.

One of Bhutan's two stamp designers, a man named Tikacchetri, has a simple outlook on the market that reaches far beyond the small kingdom's borders: "If we produce beautiful stamps, they will sell."