They are the iconic cities on everyone's travel list and draw many millions of tourists each year.
But according to these disgruntled tourists, they don't deserve the honour.
A traveller on Quora recently asked what people thought were the world's most overrated tourist destinations and boy, did the floodgates open.
Furious travellers unleashed their fury on famous cities, from London and Berlin to Auckland and Sydney, explaining exactly why they will never, ever return, news.com.au reports.
Here is some of what they had to say about the City of Sails and other popular travel destinations.
AUCKLAND
Auckland is usually well-liked by tourists, but not Yollie Estrella.
The traveller conceded the New Zealand city was very clean and the locals were laid-back and approachable, but that's where her praise ended.
"This city bored me out of my wits," she said. "The malls are closed very early, like 6pm I think.
"No museums; at least not for adults. No theatres. You just walk and walk. Had plenty of time for people-watching."
She said there was nothing to see except Waitematā Harbour, which she deemed "okay".
"We didn't even go to the tower anymore because from a quick survey, there wasn't really any picturesque view to look at," she said.
"Good thing we only stayed for a day there and moved to Matamata to go to Hobbiton, which was amazing if you're an LOTR [Lord of the Rings] fan."
SYDNEY
Traveller Yollie Estrella, from the Philippines, took aim at our Harbour City.
"Apart from the Opera House and the Harbour Bridge, it is like any metropolis — nothing remarkable except a whole facade of colonial styled buildings," she said.
"Mostly expats, hardly any locals to interact with and everyone is in a hurry."
She didn't stop there.
"Bondi Beach is overrated for me, maybe because I am from the Philippines, and I did not appreciate what is the hype about it," she said.
Ouch.
On the upside, she liked Melbourne: "More relaxed, people are friendly, very safe to explore. I specially enjoyed strolling around Victoria Market."
SINGAPORE
Boring, expensive and plastic is how Kushal Kaundinya described Singapore.
"Singapore would the most overrated travel destination," the traveller from Hyderabad, India, said.
"I have been to Singapore for my honeymoon, the first places we visited were Kuala Lumpur and Genting Highlands in Malaysia.
"Coming from them, I found Singapore to be completely lifeless, the places is artificial. The places like Gardens by the Bay for all the beauty it comprises is completely man-made and plastic.
"The Singapore Eye is another boring imitation of the already boring London Eye.
"The casinos were much less expensive and much more fun in the Genting Highlands than the Marina Bay Sands.
"Singapore is boring, expensive, highly overrated and plastic. The only good time we had was on the cruise which originated from there."
NEW YORK CITY
It is the most visited city in America, with 13.1 million international tourists arriving in 2017.
But not everyone's a fan of New York.
Traveller Samuel Xie was particularly unimpressed by the city's famous Times Square.
"As a 'square' it's pretty terrible, as many roads cut through it and make it not the most enjoyable experience for pedestrians," he said.
"Additionally, the presence of tall buildings provides a lot of shade on the square, which isn't very popular unless the sun is particularly strong that day.
"The square is small and crowded and has little historical value and is only popular from culture. It's a great way to look at advertisements, though, if that's what you like.
"On the bright side, there is a nice Shanghai-style dumpling shop nearby.
"The rest of New York is quite nice, although the subway system needs massive improvements."
PARIS
There wasn't much love for the City of Love from Brazilian traveller Rodrigo Gil.
"The city is dirty, the streets ALL look the same, the city is also too crowded and not really safe," he said.
"So nice to see that a lot of people agree with me on that. They really have some nice monuments and Louvre is awesome, but there is also a lot of homeless people, the lines are huge for some main attractions and people wanting to sell you souvenirs all the time on the main places of Paris."
VENICE
Venice is so popular it's actually struggling with the volume of tourist it attracts — the city of just 55,000 residents cops about 30 million tourists a year.
But traveller Samuel Xie doesn't get the appeal.
"Venice is also terribly overrated with little to do," he said.
"Some of the islands on the outside which you have to take a ferry to are not interesting at all and lack historical charm that the rest of Italy has in many parts.
"Florence is much better, with nice walkable areas and (in my opinion) a better hotel selection for less. Additionally, you can find plenty of good food in Florence."
Traveller Natalia Sevilla, from Colombia, agreed.
"[Venice is] expensive, you get scammed, you get stressed because you can't walk as you have tourists rubbing up against you.
"The city smells bad, and Italians don't give a s**t about how decayed and falling apart everything is."
SANTORINI
OK, it's not a city, but this famous Greek island is a bucket list staple, and its famous white churches topped with blue domes are a major drawcard for tourists.
But those are actually hard to find, Samuel Xie said.
"There are multiple 'copies' and the postcards show all of them, so it's hard to find the exact one," he said.
"When you get there, you'll have to shove your way through a throng of tour groups. The sunset is nothing particularly memorable; nice, but a two-hour wait? No thanks.
"The island is mainly tourist shops and not too nice. If you have been to Hawaiian or Floridian beaches, the beach there will be disappointing."
LONDON
Natalia Sevilla, from Colombia, was merciless in her appraisal of London, the world's third most visited city in 2017.
"Annoying, expensive, thinks of itself as the epicentre of the universe," the government worker said. "It's actually LAME.
"Pompous locals love to tell you, 'When a man is tired of London, he's tired of life'. I would correct them and say, 'When a man is tired of London, it's because that man has good taste and has travelled to less overrated much more exciting destinations!'"
Yowza.
But, there's hope for the UK yet: "If you want a nicer UK experience, go to Edinburgh in Scotland, or old northern industrial cities in England," Natalia said.
"Much more interesting and less irritating than London, with actual English people, and with easygoing attitudes."
AMSTERDAM
It's a picture-perfect city rich with history and things to do — including things that are illegal at home, if you know what we're talking about — so what problem could anyone possibly have with Amsterdam?
Natalia Sevilla found a few.
"So you go there, you head into the shrinking, dying red-light district, it's nothing outta this world," she said.
"Plus very annoying backpackers getting high! Then you say, OK, enough of this … you walk down the main avenue towards the royal palace, and hang around Rembrandt Square and you can't breathe because there are bikes, tourists, everywhere!"
Oh, she's not finished.
"You start looking for Dutch people and you don't find them, everyone is a tourist or a worker who just goes there because they work there so they have to put up with it," Natalia continued.
"You visit the Anne Frank's house and find that there is a line and you'll likely have to wait for hours! Then you visit some interesting museums and after three days you're pretty much ready to leave!"
Helpfully, Natalia suggested an alternative: Belgium, which she said was the best-kept secret in western Europe. She recommended the Belgian cities of Brussels, Antwerp and Ghent.
DUBAI
As well as being a major air transport hub, the glittering Emirati city draws about 16 million tourists a year.
But they're not all fans. Here's Natalia again: "Plastic air-conditioned s**thole in the middle of the desert.
"What can you do in Dubai besides try to stay indoors so you don't melt in the horrible heat? "Go shopping, or go ski in the fake ski slope with the fake snow!"
She said she preferred Jordan. "It's more authentic! Sadly Syria used to be beautiful, war has ruined it."