Traveling is one of the most meaningful experiences you can have in life. It's an opportunity to see the world differently and learn about new cultures.

But what are the cities you must visit before you die? It can be hard to narrow down. As travel journalist of over 20 years, I recently interviewed more than 50 travel enthusiasts, experts and agents. I asked each of them for their No. 1 picks.

Here are the most popular answers:

1. Paris, France

Paris, the City of Light, was by far the overwhelming favorite.

"I love the ambiance, culture and overall romantic vibe," says Susan Sherren, founder of luxury travel-planning service Couture Trips. But crepes and croissants barely scratch the surface of what the city has to offer.

Paris is made for strolling and magical scenery, be it the Eiffel Tower, the Louvre, or lesser-known spots like the Musée de l'Orangerie, where you can see a large collection of Monet murals.

Love shopping? Head to the exclusive boutiques on Île Saint-Louis. On a honeymoon? Take a romantic cruise on the peaceful Canal St. Martin.

2. Rome, Italy

The Eternal City's history makes it a truly special destination.

"Visiting the Vatican and Sistine Chapel should be on your list, right above indulging in pasta with a bottle of Brunello di Montalcino wine," says Kaleigh Kirkpatrick, founder of travel-planning service The Shameless Tourist.

In addition to Rome's many famous pizzerias (Kirkpatrick recommends Pinsere) and its once-in-a-lifetime sights, she always tells clients to check out the underground ruins.

"Rome presently exists with three older 'cities' buried underneath, and archeologists have uncovered numerous churches, homes and aqueducts that tourists can visit," she says.

Tap into Rome's history by taking a tour of Parco degli Acquedotti, a public park right outside of the city center, or see the underground catacombs that date back to the second century.

3. New York City, U.S.

Jonathan de Araujo, owner of The Vacationeer Travel Agency, calls the Big Apple "a city of superlatives." 

"It has the best pizza, the best bagels, the best cheesecake, the best shows, and so much more," he says.

On top of classic fixtures like the Empire State Building and Times Square, he recommends the 9/11 Memorial Museum, too. "It's now as much a part of New York City history as the Statue of Liberty," he says.

Other sites to check out: the New York Public Library, the Metropolitan Museum of Art, the New York Botanical Garden and the rotating schedule of award-winning Broadway shows.

4. Cape Town, South Africa

Tom Marchant, founder of luxury travel company Black Tomato, calls Cape Town "the perfect destination for thrill seekers."

"The city's views can be taken in from many angles, such as hang gliding over Table Mountain, driving over the hair-raising Chapman's Peak, or staying in a cliffside villa," he says.

Cape Town's natural splendor is best witnessed in the Cape of Good Hope National Park, he adds, "which can be explored via kayak, or Boulders Beach, home to the infamous penguin colonies."

If you aren't looking for that kind of adventure, there are also a number of fun, low-key options: "The towering cliffs and peaks of the region are ideal for picnics in remote locations, while Long Street and Cape Malay come alive for dinner and nightlife."

5. Rio de Janeiro, Brazil

"No other city on earth combines natural beauty, cosmopolitan glamour, an interesting food scene, vacation beach vibes and fabulous nightlife all in one," says Manny Salorio, founder of Go Ask a Local.

It also tends to be more inexpensive compared to some of the other cities on this list.

You can spend your entire trip on the iconic Copacabana and Ipanema beaches or visit world-renowned destinations like Christ the Redeemer (the famous Art Deco-style statue of Jesus), and the Maracanã stadium, one of the world's largest soccer stadiums.

The Tijuca National Park, the world's largest urban forestland and home to over 350 animals, offers amazing sights on a Jeep or ATV tour.

And don't forget to explore the city's vibrant restaurant and bar scene, where you can dance to live Bossa Nova and Samba music.

6. Tokyo, Japan

For cosplay fashion, futuristic technology and Buddhist temples, head to Tokyo. The vibrant city is full of iconic sights, like the 2,080-foot-high Tokyo Skytree and the ancient Senso-ji temple.

Cultural experiences include participating in a tea ceremony or wandering the narrow, dive bar-lined streets of Golden Gai.

But even an average dinner out feels special in Tokyo, says Jack Ezon, founder of travel agency EMBARK Beyond.

"Whether it's the art of anticipatory service, obsessive cleanliness or lofty culinary experiences, Tokyo delivers the ambiance of any world capital with a wholly unique approach," he says.

7. Istanbul, Turkey

Known for its Byzantine architecture like the Hagia Sophia, Ottoman cuisine, and the Grand Bazaar, a covered market with over 4,000 shops, Mind Over Matter Travel blogger and full-time backpacker Elaina Vieira calls Istanbul "a must-see destination for everyone."

"The first word that comes to mind when I think of Istanbul is 'chaos,' but in a good way," she says.

"When exploring the city, travelers will experience a sensory overload of different sights, sounds and smells that just fuel the excitement to explore further."

Sharael Kolberg is a travel writer with more than 20 years of experience. She has written for U.S. News & World Report, Sunset magazine, Outside magazine, LonelyPlanet.com, Forbes, Thrillist and many others. Follow her on Twitter @sharaelkolberg.

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