Anyone who sets foot outside the United States, or even flips through a guidebook to foreign lands, is sure to run across references to World Heritage Sites. But for most of us Americans it's a phrase every bit as exotic as sladoled, the Serbo-Croatian word for ice cream. Of the 754 World Heritage Sites designated by UNESCO, the cultural arm of the United Nations, a scant 20 are in the United States. Yellowstone Park, Independence Hall, and the Taos Pueblo are among the few spots that take their rightful place alongside the pyramids, the Great Wall of China, Victoria Falls, Old Havana, Machu Picchu, the Great Barrier Reef, and the Bauhaus buildings of Dessau, Germany.

That's not because we have fewer sites that meet UNESCO's criteria of 'outstanding universal value.' Nor is it some politicians' deep suspicion of the U.N., since these places are selected by an international committee independent of UNESCO. It is be-cause World Heritage sites must be nominated by the country in which they're located, and that country must have already made efforts to protect these monuments, notes Jonathan B. Tourtellot, a columnist for National Geographic Traveler (October, 2002). American officials are skeptical of an international program that sets standards for preserving historic and natural wonders.

Other nations are eager to see their magnificent landscapes and charming towns recognized as world treasures. Mexico has 23 sites on the list, while Portugal, a country smaller than Ohio, has 12 designated sites that Tourtellot says the Portuguese never tire of bragging about.