The world is full of beautiful destinations that a lot of people are desperate to see, but many of them are increasingly under threat from both environmental and man-made challenges. While experiences in places as diverse as the Galapagos, the Great Wall of China and even the canals of Venice have been capturing people's hearts and imaginations for years, it is important to visit them responsibly in order to protect them.

Click through the gallery to discover some of the world's last-chance travel experiences...

Diving or snorkelling the Great Barrier Reef is on many travellers' bucket lists and it's easy to see why. Stretching over 1,430 miles (2,300km) down Australia's east coast, the reef is the largest living structure on Earth and is even visible from space. The UNESCO World Heritage Site is home to 1,600 species of fish, 600 types of coral and 180 different types of shark, and exploring the crystal clear waters and brightly-coloured reef is truly a once-in-a-lifetime experience. 

But the world's largest reef system – widely deemed one of the seven natural wonders of the world – is under threat from rising water temperatures, mainly caused by climate change. Marine heatwaves have already triggered four mass bleaching events in a mere seven years and while coral can recover, that's only if temperatures drop and conditions return to normal. Other climate change-related issues impacting the Great Barrier Reef include ocean acidification, severe weather and habitat changes.

As many as 30 million visitors flock to the 'Floating City' of Venice each year to marvel at the water-lapped palazzos, admire the picture-perfect Piazza San Marco, take a gondola down one of its 150 canals and walk over some of the 400-plus bridges that run between the lagoon's 118 islands. Founded in the 5th century, Venice became a maritime superpower in the 1100s and its famous landmarks such as the Rialto Bridge soon captured the public imagination after being immortalised in the artworks of Titian, Canaletto and Monet, among many others.

Venice is now a victim of its own success with mass tourism, rising sea levels twinned with sinking foundations, and record high temperatures all threatening the Floating City. Various measures, such as a ban on cruise ships, a €5 (£4.25/$5.35) entry fee for daytrippers, banning loudspeakers and limiting tour groups to 25, have been introduced to help Venice protect its canals and better manage visitor numbers. Meanwhile, its MOSE flood defence system has helped the UNESCO World Heritage Site keep flooding at bay since its construction in 2020.

Read more about the fascinating story of Venice here

Orangutans are only found in two parts of the world – the Indonesian island of Sumatra; and on Borneo, the third largest island in the world. The world's largest tree-dwelling mammal, the orangutan – whose name derives from the Malay term for 'person of the forest' – is highly intelligent (it shares 96.4% of our genes) and very gentle, making the creature fascinating to watch in the wild. 

Orangutans are best viewed at sanctuaries and rehabilitation centres, which work to protect the endangered creatures. The gentle giants of the rainforest are under threat from logging, deforestation hunting and the illegal wildlife trade. A century ago it was estimated that there were 230,000 orangutans in total, but now there are said to be about 104,700 endangered Bornean orangutans, 7,500 critically-endangered Sumatran ones and just 800 Tapanuli orangutans – the most endangered great ape.

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Bolivia's Salar de Uyuni attracts some 24,000 visitors a year to see its mirror-like landscape. The world's largest salt flat is what is left behind by prehistoric lakes that evaporated long ago and is basically a thick crust of salt, which disappears into snow-capped mountains in the distance. Between December to April, the salt flat turns into what looks like a giant mirror when covered by water after rain. When the top layer dries, the surface cracks to form polygonal patterns.

Aside from salt, Salar de Uyuni is also the largest source of lithium – the 'white gold' that helps power everything from mobile phones to laptops and electric vehicles. The wider area is known as the 'Lithium Triangle' and the mineral is so valuable that Bolivia's state-owned mining company opened its first industrial-scale lithium plant nearby in 2023. Many fear that extracting lithium will lead to pollution, water shortages and soil contamination – threatening an already fragile ecosystem.

The ruins of Incan citadel Machu Picchu have captured many a traveller's imagination since its 'discovery' by US archaeologist Hiram Bingham in 1911 – having laid forgotten, except by locals, for centuries. The 15th-century site's stone palaces, terraces and temples situated at 7,972 feet (2,430m) above sea level make up one of South America's most famous and mysterious tourist attractions. While there are train options, many visitors choose to hike the challenging 26-mile (43km) Inca Trail.

One of the biggest concerns about Machu Picchu is that the UNESCO World Heritage Site is at risk of collapse – both due to natural erosion and problems related to overtourism, such as vandalism and littering. Such concerns have led to greater efforts to preserve the historic and sacred site, although the Peruvian government recently caused controversy by significantly increasing daily visitor numbers in early 2024 as the country's tourism industry struggled to recover post-pandemic. 

The Statue of Liberty is one of the world's most symbolic tourist attractions. Long synonymous with the American ideals of equality, democracy and freedom, the 305-foot (93m) statue was built in France in 1884, shipped across the Atlantic and finally mounted on its pedestal to much fanfare in 1886. Visitors can buy tickets to see stunning views of New York City from the pedestal balcony, while a select number are able to climb the 215 steps to Liberty's crown for an even better panorama.

The Statue of Liberty's location in a harbour makes it vulnerable to the elements, as highlighted by 2012's Hurricane Sandy, and some scientists have warned that it is under threat from severe storm surges. Indeed, sea levels in New York City are expected to rise between 8in (20cm) and 30in (76cm) by the 2050s; and as much as 15in (38cm) to 75in (190cm) by 2100, according to The NYC Panel on Climate Change. The statue was restored ahead of its centennial in 1986 and preservation work remains ongoing.

Attracted by its pristine beaches, the clear blue waters of the Indian Ocean and some of the world's finest luxury resorts, some 1.8 million tourists visited the island nation of the Maldives in 2023. Made up of 1,190 islands of which only 200 are inhabited, the Maldives and its surrounding waters are home to over 1,000 species of fish and more than 2,000 coral reefs – making it a diving and snorkelling paradise. The Baa Atoll – one of 27 making up the Maldives – is a UNESCO Biosphere Reserve. 

But the same crystal waters which attract so many visitors also pose an existential threat to the Maldives, where 80% of the land area is below sea level – making the island nation extremely vulnerable to climate change. Indeed, some scientists predict that the islands could be completely submerged by 2100. In a bid to mitigate the impact of the climate crisis on the atolls, the country is implementing a national adaptation plan to make them more resilient to rising sea levels and temperatures.

Churchill in the Canadian province of Manitoba is known as the 'Polar Bear Capital of the World', with an estimated 1,200 of these majestic creatures passing through the region each October to early November. Polar bears spend more than 50% of their time hunting for food and they then leave the area to hunt for seals ahead of winter. Beluga whales, Arctic birds and owls and Arctic wolves are among other native species here, with the Northern Lights also visible for much of the year. 

Hudson Bay's polar bears are now at risk of starvation as climate change prolongs the period without Arctic sea ice, so the animals cannot access their main source of prey – ringed and bearded seals – as easily. This means the bears are now having to work much harder to stay alive as they stretch their fat reserves for several more weeks each year. Indeed, Hudson Bay alone saw a 30% drop in its polar bear population, from 1,185 bears in 1987 to 806 bears in 2011.

Ancient Olympia, in the so-called 'Valley of the Gods' on the Peloponnese peninsula, is one of Greece's top archaeological attractions. The complex was once the most celebrated sacred site of Ancient Greece and is best known as the birthplace of the Olympic Games, which were held here every four years between the 8th century AD and the 4th century BC. While only the ruins of the once grand buildings remain, visitors can still easily visualise how important the site was in the ancient world.

The Olympic flame is still ceremoniously lit here ahead of each Games, including for Paris 2024. But unfortunately it's fires of a far more serious kind that also keep Olympia in the headlines. In 2007, wildfires reached the edge of the site and while none of the ruins were damaged, much of the surrounding landscape was severely impacted. Greece has continued to see extreme hot weather and wildfires since, exacerbated by the climate crisis and threatening historic sites across the country.

Bordeaux is home to the largest fine-wine vineyards in the world, with wine-making in the southwest region of France dating back more than 20 centuries. Indeed, wine is very much part of everyday life here, with at least 6,000 chateaux – possibly more, as estimates vary – producing more than 600 million bottles each year. When not touring the vineyards and sampling the local tipples, tourists can enjoy medieval cities, historic villages and other architectural treasures.

Bordeaux is known for using traditional winemaking methods honed over the centuries. Yet viticulture is subject to changing weather conditions just like agriculture, and the impact of climate change is already being felt. Ironically, the more recent warmer, drier summers and cooler, wetter winters could make better wine. But extreme heat and drought fears, along with changing consumer trends, mean winemakers are already uprooting their vineyards and repurposing the land for other uses.

The ice-capped peak of dormant volcano Mount Kilimanjaro is the highest mountain in Africa at 19,340 feet (5,895m), making it one of the world's most popular climbing destinations. Some 35,000 people try to climb it each year, but while no technical climbing skills are needed, many suffer altitude sickness. Those who do successfully manage the five to nine-day hike and descent of the mountain are rewarded with views of stunning sunrises and sunsets, numerous different landscapes and snowy glaciers. 

Kilimanjaro's ice cap is fast retreating, having already shrunk by 90% in a century. While some of the problem is related to global warming, the issue is greatly worsened by deforestation for agriculture, firewood and charcoal making. The resulting lack of vegetation dries out the mountain and means there is less precipitation, and less water, for both the glaciers and the local people. The UN predicts that Kilimanjaro's 11,700-year-old glaciers will vanish entirely by 2050.

Discover the world's oldest landmarks still attracting the crowds today

Legend has it that a mythical princess living on Komodo had two sons (one human, one lizard) who learned to live in harmony on the 'island of dragons' – and local people continue to live in harmony with these impressive creatures. Wildlife watchers wanting to admire and observe the world's largest lizards, which grow to an average length of up to 10 feet (3m), in their natural habitat can do so at Indonesia's Komodo National Park. The endemic rat, orange-footed scrub fowl and yellow-crested cockatoo are also native here.

The Komodo dragon is deemed endangered by the International Union for the Conservation of Nature, which estimates that there are less than 1,400 adults left in the world. The majority of the creatures are in Komodo National Park, where they are fairly well protected, but they remain at risk of potential habitat loss due to a rapidly changing climate. In 2019, Indonesian authorities announced they'd be closing the park to tourists for a year to protect the dragons, but the plan was later shelved.

The Great Wall of China is one of the world's greatest feats of engineering, stretching 13,171 miles (21,196km) east to west from Shanhaiguan province by the Yellow Sea to Jiayuguan, near the Gobi Desert. It was built between the 3rd century BC to the 17th century AD as a great military defence project along the northern frontier. While some sections are in ruins or have collapsed altogether, it is still a remarkable sight that was designated a UNESCO World Heritage Site in 1987. 

Thousands of years on, the fortification is now under threat from both man and nature. Over a third of the Great Wall is thought to have already disappeared, with just 8% considered well-preserved. Part of the problem is the ravages of nature, another is reckless behaviour by some of the 10 million yearly visitors, but other issues include locals using parts of it to build houses and animal pens. In 2023, part of it was severely damaged by construction workers who used an excavator to create a shortcut through it.

The Galapagos Islands have long been a mecca for wildlife spotters, unsurprisingly given that it was here that Charles Darwin formed his theory of evolution by natural selection. UNESCO describes the area as a 'living museum and showcase of evolution' thanks to the development of unusual animal life. The most famous residents here are the giant tortoises, which on average live over 100 years and inspired the name of the islands – 'galapago' being a Spanish word for tortoise.

Despite having some of the world's most protected wildlife, the Galapagos face several environmental challenges with the introduction of invasive species – both deliberate and inadvertant – posing a particular problem to the islands' biodiversity. Another threat is El Nino, the climate pattern that can change population numbers of almost all species in the Galapagos in a short space of time. Protecting the species is also vital for maintaining the islands' local economy, which relies on ecotourism.

The Amazon rainforest is the world's richest and most diverse biological reservoir, home to more than three million species and over 2,500 tree species. Covering 2,300,000 square miles (6,000,000sq km) and spanning nine countries, with the majority in Brazil, a new species of animal or plant is thought to be discovered in the Amazon each day. Visitors can best explore the rainforest by taking a boat trip down the Amazon River, or staying in a jungle lodge within or close to nature reserves.

Yet despite the vital role that the Amazon plays in sustaining our planet – an estimated 150-200 billion tonnes of carbon are stored in the rainforest's trees and soils – it still faces existential threats. Indeed, climate scientists recently estimated that up to 47% of the 'planet's lungs' could be put at risk of rising temperatures, deforestation, droughts and fires by 2050. In positive news, after years of unchecked development, moves are underway to get deforestation to zero by 2030, with Brazil among the signatories. 

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