What follows is a list of countries. Alongside those countries is what I have to the best of my abilities determined to be the single most-visited attraction in that country. 'Attraction' is the operative word; most places I looked at excluded places like shopping malls and casinos and I just kind of had to cobble together a know-it-when-you-see-it personal definition. (One place excluded the Mall of America. I disagree. When I was there in May, I confirmed with a mall employee that there are people that fly into the United States, stay overnight, go to the mall, and then fly home, the mall being all they do in the United States. The airport is literally right across the street. I call that an attraction.) Otherwise, I'm kind of going by what's given to me.
Why? Because I can. Why do I post half the content around here? For lack of a better term, intellectual masturbation. Facts for the sake of facts. The kind of thing that makes onlookers go 'Well, that's rather interesting, but wow, you've got way too much time on your hands.'
This was a lot more difficult than anticipated, though. This is a surprisingly inexact thing; numbers were not always supplied and so in several cases I had little choice but to follow a consensus; the link being a reflection of same. The list of countries is not complete- it was a total bear to pull more than one country's top attration off of any one link- but it's as large as I could make it before exhaustion set in. Really, I'm a bit shocked that this kind of thing isn't vastly better-documented than it is. You would think that this would be the kind of thing that gets trumpeted in the travel industry. Granted, a lot of countries on Earth aren't exactly known for tourism, but lack of documentation was a problem even with the countries that actually expect tourists on a regular basis-- Hungary, Uruguay, United Arab Emirates, Belgium, Czech Republic, Romania, Thailand, Chile, Costa Rica, Malaysia, Argentina, Morocco. I never was able to get anything resembling confirmation for any of them.
The countries are not in competition with one another; even if I wished that the case, that would be near-impossible, except to say that number one overall is Times Square of the United States. Speaking of, if the Americans want a state-level equivalent, someone else has you covered already.
And just to clarify: most-visited does not mean best.
Sound good? Here we go.
Anguilla- Shoal Bay East
Aruba- Natural Bridge, never mind that the bridge actually collapsed in 2005; people go look at the rubble
Australia- Great Barrier Reef
Austria- Schonbrunn Palace, Vienna
Bahamas- Two places are equally claimed: the Royal Naval Dockyard and the Bermuda Aquarium, Museum and Zoo. I'd probably give it to the aquarium if forced to guess.
Bangladesh- Cox's Bazar, Dhaka
Barbados- Harrison's Cave
Belize- Ambergris Caye
Bolivia- Yungas Road, and you people are absolutely fucking sick
Botswana- Okavango Delta
Brazil- Christ the Redeemer statue, Rio de Janeiro
Cambodia- Angkor Wat
Cameroon- Waza National Park
Canada- Niagara Falls
Cayman Islands- Can't call it one way or the other. It's either the Turtle Farm or Stingray City. Gun to my head, I'd guess the Turtle Farm.
China- Great Wall of China
Colombia- Chicamocha National Park
Croatia- Plitvice Lakes National Park
Denmark- Tivoli Gardens, Copenhagen
Ecuador- Galapagos Islands
Egypt- Pyramids of Giza
Finland- Linnanmäki Amusement Park, Helsinki
France- Euro Disney, Paris
Gambia- Abuko Nature Reserve
Germany- Neuschwanstein Castle
Greece- Acropolis, Athens
Guam- Two Lovers Point
Guatemala- Xocomil/Xetulul, Retalhuleu (Lonely Planet Guatemala)
Honduras- Bay Islands
Hong Kong- Hong Kong Disneyland
Iceland- Blue Lagoon
India- Taj Mahal, Agra
Ireland- Guinness Storehouse, Dublin
Israel- Western Wall, Jerusalem
Italy- Vatican City, or if you count the Vatican separately, the Roman Coliseum, Rome.
Jamaica- Dunn's River Falls, Ocho Rios
Japan- Tokyo Disneyland, Tokyo
Kenya- Maasai Mara Reserve
Kuwait- Failaka Island
Macedonia- Lake Ohrid
Malawi- Lake Malawi
Mali- Bandiagara Cliffs (aka Dogon Country), Mopti (Mali: the Bradt Travel Guide)
Monaco- Rock of Monaco, Monte Carlo
Mongolia- Terelj National Park
Namibia- Etosha National Park
Nepal- Mount Everest
Netherlands- Efteling, Kaatsheuvel
New Zealand- Sky Tower, Auckland
Norway- Floibanen, Bergen
Oman- Nizwa Fort, Nizwa
Panama- Panama Canal
Peru- Machu Picchu
Portugal- Nothing overly certain here; my best reckoning is the National Coach Museum, Lisbon
Russia- Hermitage Museum, St. Petersburg
Saudi Arabia- Kaaba, Mecca
Senegal- Goree Island
Seychelles- Beau Vallon Bay, Mahe Island
Singapore- Sentosa Island
Slovakia- Aquacity, Poprad
Slovenia- Postojna Caves
South Africa- Victoria and Alfred Waterfront, Cape Town
South Korea- Everland, Kyonggi-Do
Spain- Alhambra, Granada
St. Lucia- Pitons
Sweden- Liseberg Nojespark, Gothenburg
Switzerland- Matterhorn, Zermatt
Tanzania- Serengeti National Park, though it and Mount Kilimanjaro help make up what is more commonly referred to as the 'most popular' attraction, the "Northern Circuit"
Turkey- Hagia Sophia, Istanbul; the link shows a museum exhibit that overtook it, but that exhibit has since closed
United Kingdom- Trafalgar Square, London
United States- Times Square, New York City
Venezuela- Angel Falls
Vietnam- Halong Bay
Zambia- Victoria Falls
Zimbabwe- Also Victoria Falls
If anyone has corrections (with numbers; you're certain to find disagreeing sites), or if anyone can fill in some of the countries I didn't get, if you put it in the comments, that'd be great. If you do launch a search, though, note that there is a huge difference between "one of the biggest attractions" and "the biggest attraction".