These are the 20 places in the world you must visit this century

While people may have been flocking to the Pyramids since, well, 5,000 years ago, Smithsonian Magazine has put together a list of the top 20 new tourist destinations future generations might add to their bucket lists.

Sites of recent scientific, artistic and historical importance such as CERN, home of the God-particle, and the world's fastest rollercoaster in Abu Dhabi are among those that make the cut.

Several natural wonders that might not be around for much longer like the western lowland gorillas of the DRC and Rwanda and Alaska's Mendenhall Ice Caves are also included.

For the Smithsonian's list of places and events that have helped define the 21st century to date, read on:

1. The world's largest cave, Hang Son Doong in Vietnam, the extent of which was discovered in 2009

2. Cern Laboratory, Switzerland, home of the God Particle

3. Virgin Galactic's Spaceport America, New Mexico

4. The last 800 western lowland gorillas (DRC, Uganda and Rwanda)

5. The Alma telescope in Chile which captures the world's starriest night sky

6. The shrinking glaciers of the Mendenhall Ice Caves, Alaska

7. Ferrari World in Abu Dhabi, the world's fastest rollercoaster

8. Cayman trench in the Caribbean Sea, the deepest dive in the world

9. The Museum of Islamic Art, Qatar, opened in 2008

10. Copenhagen's Noma, the world's best restaurant

11. Havana, Cuba, the rapidly changing "trade sanction-preserved time capsule"

12. Leicester, recently discovered resting place of King Richard III

13. The flower shrine of Haifa, Israel

14. Icestock music festival, Ross Island, Antarctica

15. The 'throbbing' temple of New Delhi, India, opened in 2005

16. John Muir Way, Falkirk

17. The Door to Hell in the Karakum Desert, Turkmenistan, a natural gas cavern discovered in 1971

18. The Gates of Heaven skywalk, Tianmen Mountain, Hunan Province, China

19. A hair-raising cross country trip on Ecuador's railways, taking in one of the most biodiverse environments on the planet

20. Ellis Island Hospital, New York, reopened in 2014

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