After a recent trip to Stonehenge, I shared photos with my parents and they paid special attention to the arching pedestrian walkway prohibiting visitors from getting closer than 30 feet from the stones. Recounting a visit to the ancient spot on their honeymoon, my parents described walking through the prehistoric monument and running fingers over the mysterious rock formations. Despite standing since the Bronze Age, the burial mounds were the target of graffiti artists in recent decades, forcing officials to rope off the landmark in 1977 and effectively giving future visitors limited access and distant vantage points.
Around the world, other important landmarks have fallen victim to vandals and environmental dangers causing damages beyond repair that could soon make tourist travel impossible. Here are the destinations our Deal Experts are bumping to the top of their bucket lists to experience in their full glory before it's too late.
Peru's Machu Picchu
Dating back to 1430 AD, the former Incan city hosts thousands of visitors each day and has seen severe erosion to the stone steps, platforms and walls as a direct result. April brings temporary closures to two parts of the Peruvian "New Wonder of the World." The first half of the month will see the closing of Huayna Picchu, the steep peak rising behind Machu Picchu and home to the Temple of the Moon, one of the three major temples in the area. Cerro Machu Picchu, the challenging trail directly across the ruins from Huayna Picchu, will be off limits for the last 15 days of the month.
Step back into the ancient world of the Incas with seven days in Lima, Cusco and Machu Picchu. The package includes tours, meals, a guide and all entrance fees while saving $500 per person.
The northern Italian island is arguably the most romantic city in the world. Cruising the Grand Canal by gondola may be popular with lovebirds but the "floating city" is in danger of being swallowed by the Adriatic Sea. Although Venice has been sinking for centuries, severe flooding has sped up the process five times as fast as previously predicted, compromising the foundations of the charming marble buildings and walkways.
Travelzoo members enjoy exclusive room upgrades, dining credit, early check-in and late check-out at Locanda Vivadli. The 4-star waterfront hotel is five-minutes from St. Market's Square and the terrace offers panoramic views of the city.
The Dead Sea, bordering the West Bank and Jordan
The planet's saltiest body of water is 1,300 feet below sea level -- the lowest point of the world. For generations, travelers seeking a wide range of health benefits found within the mineral-rich mud have flocked to the rocky beaches feeding from the Jordan River. Most of the river's water has been diverted for agriculture and drinking water in neighboring countries. The man-made strain combined with the water's natural salinity means the sea evaporates faster than it can be replenished.
This seven-night escorted tour through Israel includes one night at the Prima Spa Hotel Dead Sea as well as meals, transfers and stops in Tel Aviv, Jerusalem and Northern Israel while saving visitors over $195 per person.
The Swiss Alps
At a lower altitude than the Rocky Mountains, the European Alps' glaciers and ski resorts are more susceptible to the effects of global warming. Temperatures at the summit rose twice as much as the global average since the 19th century, and experts predict the famed snow caps will completely disappear by 2050.
Basel, on the Swiss border near France and Germany, is one of Europe's best-preserved old towns. Hotel Victoria is next to the train station and an hour's ride from the base of The Alps. Travelzoo members receive $85 in exclusive extras at the hotel including upgraded rooms and daily breakfast.
India's Taj Mahal
Crowds and air pollution are eating away at the white stone façade of the UNESCO World Heritage Site. Officials in India are considering closing the 17th-century landmark to the public sometime in the next five years - meaning the domed symmetrical symbol of undying love will only be visible from afar.
In addition to a sunset tour of the Taj Mahal, this six-night India vacation guides travelers through Delhi, Agra, Bharatpur and Jaipur, saving $600 per person.
Australia's Great Barrier Reef
Portions of the Great Barrier Reef are believed to be over 20 million years old and home to 215 species of birds, 30 kinds of marine mammals, 10% of the world's total fish population and hundreds of snakes, sea turtles and sea urchins. In just 30 years, half of the reef has vanished, a casualty of increased acidity levels in the ocean. By 2070, the Australian Greenhouse Office predicts water temperatures rising as much as 6 degrees, causing mass coral bleaching when combined with pollution and irresponsible tourism practices. The only living thing visible from outer space could be extinct in our lifetime.
This Great Barrier Reef tour includes international flights, five nights in Cairns and a cruise to the reef for $1699 per person. The package also includes a visit to the adjoining Daintree rainforest and day trip to Green Island, the only coral cay on the reef with a rainforest.
Tanzania's Mount Kilimanjaro
The ice caps on Mount Kilimanjaro, Africa's tallest mountain, started receding in 1912, and snow stopped accumulating in 2000. The exposed soil absorbs heat quickly, speeding up the melt, and scientists believe the last glacier will evaporate within 15 years. Those looking to climb the volcanic mountain should make sure guides are qualified and follow environmentally friendly.
Flying in and out of Kilimanjaro Airport for this 12-night safari to Tanzania and Kenya gives travelers bird's eye views of the picturesque range and saves more than $500 per person. Game drives at Samburu Game Reserve and Masai Mara National Reserve offer the once-in-a-lifetime chance to see Africa's Big Five game animals in person, including the critically endangered black rhinoceros.
The Florida Everglades
Encompassing 2.5 million acres of swamps, savannas and mangroves, the Florida Everglades are the only place on the planet where alligators and crocodiles coexist. Only a fifth of the wetland is protected as a national park, and over the past century, urban development and the introduction of foreign species, particularly the Burmese python, have wreaked havoc on the region's wildlife. Endangered species including manatees, green sea turtles and the Florida panther call the Everglades home and could be wiped out if the changes to the ecosystem are not reversed soon.
Take an airboat tour of the Everglades to see the incredible wildlife in its natural habitat. Half-price tours are available daily through April.
Skimming just eight feet above sea level, the Maldives is the lowest-lying country on the planet. As sea levels continue to rise, the 1,192 islands that make up this beautiful nation face the threat of disappearing below the surface within the next century. To combat the surging Indian Ocean, the government built a seawall around Male, the capital, and began purchasing land in other countries for citizen relocation.
Vacations at the 5-star Jumeirah Dhevanafushi, stretching across two islands, including air from Hong Kong, meals, transfers and non-motorized water sports are discounted $1,210 per person.
Elisabth Barker is a deal expert at Travelzoo and based in New York. Travelzoo has 250 deal experts from around the world who rigorously research, evaluate and test thousands of deals to find those with true value.
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