Finally, there's a hybrid of the two: a "one and done" travel experience so epic and so awesome and so life-altering, it really only needs to be completed once. After that, you're either too high on adrenaline or too full of food or too sick of tourists to EVER do it again.

Allow us to show you what we mean.

1. Ride to the top of the Eiffel Tower

Watching the City of Light sparkle beneath you is pure magic, but The. Line. Is. Insane. Plus, you'll find much more authentic versions of Paris on the ground.



2. Go clubbing in Las Vegas

Don't hate us, but that city is expensive. And a veritable hellhole. Capture the rush of dancing on a table to "Sexyback," and then stick to your neighborhood dive bar for the rest of your life.



3. Shop Harrod's in London

Well, you shouldn't visit just once... you should move in and never leave. While we wish we could do this, it's not a very productive way to spend your short time in London.



4. Climb Mount Kilimanjaro

...just mostly for the sake of your quadriceps. If you're capable of summiting this monster more than once, then by all means go for it.



5. Visit the "coffee shops" in Amsterdam

Check it off your list. But let's face it: nobody needs to inhale that many substances in one trip EVER again.



6. Stay at a Caribbean mega-resort

Those themed water slides are pretty darn fun, and poolside sandwiches are prime. But the guilt of contributing to the commercialization of such a pristine natural landscape creeps in fast, and you'll wish you were in an eco-friendly hut on a secluded cay.



7. See the Sistine Chapel

You've heard about Michelangelo's painstaking labor, and you should see its fruits. But no cameras? No classical music? No trumpets and fanfare? Not worth a second visit.



8. Cruise Halong Bay, Vietnam

You'll never be able to match the thrill of that first flip off the boat deck... which is why you should give up now and head to a more remote, less intoxicated part of beautiful Vietnam.



9. Run with the bulls in Pamplona, Spain

You can really only do this once, because once could potentially kill you.



10. Stay at The Ranch at Live Oak in Malibu, California

A week of "luxury bootcamp" at one of the best spas in the world entails group yoga, private massages, organic meals and queen-size beds. By the end you'll be so fit (and so broke!), you won't need a return trip for years. At least Malibu sunsets come free of charge.



11. Visit the rim of the Grand Canyon

Standing on the edge at sunrise will make you feel utterly tiny and awestruck. So awestruck that you'll want to book a longer stay so you can go inside!



12. Order crepes off the street in Paris

It's taste-bud-mesmerizing to watch them spread batter on a hot griddle. But when bites cost a dollar a pop, you'll realize tourists are the only ones buying them.



13. Spend spring break in Cancun, Mexico

Sun, margarita, sun, repeat. It's a renewing cycle, but after one run-through you should throw some culture into the mix with a place like Tulum.



14. Go to Oktoberfest

You've never really heard someone say they're going back to Oktoberfest, presumably because it was either too expensive, too crowded, or too liver-damaging... or perhaps all three.



15. Visit the top of the Empire State Building

It's $29 of sheer, haggling craziness, and once you've seen it you've seen it. But the more chilled-out Top of the Rock is something we'd sign up to do both morning and night, summer and winter.



16. Gorge yourself at Damnoen Saduak floating market

This Thai culinary wonderland is one of the most famous floating markets in the world. The sights, smells, chaos and tastes are overwhelming -- in a good way that leaves you satisfied for years.



17. Attend a closing party in Ibiza

Spain's party island is bonkers at the end of the season. One all-night shindig is enough to tire you for the rest of your trip, so wise travelers indulge only once.



18. Take a desert road trip

On arid highways in New Mexico, there isn't a knoll in sight, and you'll be the only car on the open road. It's exhilarating, but there are more potty stops on a southern route. And when a thunderstorm hits, you're toast.



19. Have the Guinness Storehouse experience

Ireland's most iconic beer tastes even more robust after a trip through its intricate creation process. After getting the spiel, though, go drink it in an authentic pub, as was intended.



20. Visit the Acropolis

Ancient history is humbling. However, the modern city of Athens is not a place you want to visit twice.

