I will probably never visit Prague in the Czech Republic. Though I once spent a month in India, I didn't tour the Taj Mahal. And it would take a live sighting of Shakespeare to make me return to Stratford-upon-Avon in England.
That's because I don't like crowds, the trash they leave, tour-bus fumes, full parking lots, long lines. There comes a point when it's simply not worth seeing the Louvre's Mona Lisa or Italy's Leaning Tower of Pisa if it means being pushed, squeezed, elbowed and distracted.
Beyond the annoyance, swarming tourists often contribute to the degradation of famous sites. They trample the French parterres at Versailles, short-cut switchbacks on trails at the Grand Canyon, pocket stones from Mexico's Chichen Itza, write their names on the Great Wall of China. And wherever they go, fast-food restaurants, chain motels and kitschy souvenir shops are never far behind.
To describe crowding in Venice, Italy, English historian and travel writer John Julius Norwich coined the phrase "tourist pollution." As many as 18 million people visit the Italian city a year, spawning hotels, restaurants and shops. As a result, rents and property prices have skyrocketed, driving average, workaday Venetians to more affordable housing on the mainland.
In 1951, 171,000 people lived in Venice. Now the population is about 62,000. Even if dikes are built to stem the rising sea level -- La Serenissima's other big problem -- it's estimated that there will be no native Venetians living in Venice by 2030.
Tourist pollution has also gotten out of hand at the top of the world. Near the border between Tibet and Nepal looms 29,035-foot Mount Everest, whose summit Edmund Hillary and Tenzing Norgay reached in 1953. Since then, thousands have flocked to Everest, including hundreds who make it to the top every year and others who just ogle the peak from the surrounding region.
The trail to Everest base camp is lined with hotels and tea shops, and the mountain is littered with climbing debris -- plastic bags, tin cans, syringes.
Alpinists and environmentalists have advocated closing Everest for a few years to give nature a chance to repair the fabled peak. But the idea is unattractive to local tourism providers, and political turmoil in Nepal has put the proposal on hold.
The 800,000 or so tourists who visit England's Stonehenge each year also adversely affect the site. A fence has been erected around the monument to stop vandals from spray-painting graffiti on the 4,000-year-old stone circle. Seeing Stonehenge today is hardly magical. In fact, a parliamentary committee in 1989 called the situation a "national disgrace."
Several groups, including English Heritage, the National Trust and the British Highways Agency, have proposed changes to protect and enrich the experience of visiting Stonehenge. These include the construction of a visitor center designed to blend into the landscape, creating an environmentally friendly transportation system to move visitors around the site, restoring natural vegetation and channeling the A303 highway through a 1.3-mile tunnel.
The story is much the same at other renowned places around the world.
In Italy, on a busy day in the architecturally rich medieval Tuscan hill town of San Gimignano, 160 tour buses cruise for parking places and thousands of people crowd into the historic center.
"Some sites get too famous for their own good," John Stubbs, vice president of World Monuments Fund, told me by phone. The nonprofit organization, which has its headquarters in New York, works for the preservation of endangered architectural and cultural sites.
One tourist attraction that especially concerns him is Phnom Bakheng at Angkor in Cambodia. The 9th century Hindu temple dedicated to Shiva is on a steep hill, reached by a chain of old stone steps. "It has become an obsession for tourists at sunset," he said. "There may be just a few people there in the middle of the afternoon, but as many as 3,000 between 4 and 5:30 p.m." Erosion and damage to the steps are the results.
Recently, the monuments fund and Cambodian authorities began a project to stabilize the steps and study ways to better manage crowds. Simple measures such as keeping traffic flowing in a single direction and finding alternate routes can make all the difference at ailing tourist attractions, Stubbs said.
Egypt's Valley of the Kings no longer appears on the fund's 100 Most Endangered Sites list, partly because wayside markers were installed that speed visitor circulation.
But other more drastic remedies have been suggested and implemented. These include limiting vehicular access around popular sites, as the National Park Service has done in Yosemite Valley in California.