20 places you should visit before they disappear

Earth is home to incredibly beautiful natural sites.

Unfortunately, due to climate change and human carelessness, some of them are in danger of disappearing in the next 100 years — or even sooner.

In honour of Earth day, we found 20 places all travellers should see while they still exist. From ancient Mayan ruins in Guatemala to the Swiss alps, these threatened natural wonders span the globe.

A popular destination for honeymooners or paradise-seekers, the islands of the Seychelles -- located in the Indian Ocean off the coast of Madagascar -- are vanishing because of beach erosion. They're in danger of completely disappearing in the next 50 to 100 years.

Madagascar's forests are predicted to exist only for another 35 years, due to a multitude of fires and mass deforestation.

The number of glaciers in Montana's Glacier National Park has decreased from 150 to fewer than 25, and in another 15 years, there may be none left.

Get your gondola ride in soon because Venice has been sinking for a number of years and it's showing no signs of stopping. More and more severe floods in recent years are also contributing to the disappearance of the city of canals.

A combination of too many tourists and foreign species that don't belong is threatening the ecosystem and unique native species of the Galapagos Islands, a group of islands off the west coast of Ecuador.

Africa's Congo Basin, the world's second largest rainforest, is also one of the most bio diverse areas with over 10,000 plant species, 1,000 bird pieces, and 400 mammal species. In the last few years, the 1.3 million square mile forest has been decreasing rapidly due to illegal mining, and the United Nations predicts two-thirds of it may be completely gone by 2040.

The Dead Sea, which borders Jordan and Israel, has sunk 80 feet and disappeared by a third in the past 40 years. As long as countries around the sea continue to use water from the River Jordan (the only place the Dead Sea draws its water from), the sea could be completely gone in 50 years.

The Florida Everglades have been referred to as the most threatened park in the US. Too much water, new species, and urban development are all part of the problem.

The world's largest coral reef, Australia's Great Barrier Reef, has decreased by more than half its size due to rising temperatures in the last 30 years. Increased acid pollution has also began to lead to coral bleaching, slowly turning its famed vibrant corals white. Scientists predict the site could be completely gone by 2030.

Egypt's pyramids and Great Sphinx are facing erosion from pollution. As sewage is weakening the plates they stand on, there are concerns that the pollution may eventually lead to their complete collapse.

At an impressive 2.1 million square miles, Brazil's Amazon is the largest rainforest in the world. It's home to the world's most diverse species, but expansion of agriculture could lead to the destruction of the rain forest.

The largest man-made structure in the world, the Great Wall of China has survived for over 2,000 years as a favourite must-see destination, but recent over-farming has led to nearly two-thirds of the wall having already been damaged or destroyed. The wall could be reduced to ruins by erosion in as little as 20 years.

The Maldives, an island nation in the Indian Ocean, is slowly sinking due to climate change. Scientists predict that within 100 years, it will be completely submerged.

Big Sur in California is known for offering up-close whale watching, but recent droughts and wildfires are significantly harming the coastal region and leading to fewer sightings of the mammals each year.

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