Whether you have a US trip planned or wish to understand their surprisingly different culture, here are some of the top answers.
America is larger than you think
One of the most popular topics by far was how many tourists understimated America's size.
"You can't drive across the country in 12 hours," wrote user Dodo_Whisperer1.
"You drive five hours in the US, you're basically still in the same place. You drive five hours in Europe, everyone's talking funny and the cheese is different," user KaimeiJay added.
In fact, said added another American, "you can drive 8 hours East to west and still be in Texas."
Stay on the right side of the law
On the topic of driving, one person pointed out that "each state has its own driving laws."
Another jumped in to say, not only this, but each state can have it's own laws on anything.
Age of consent, drinking, smoking, etc can vary based on state along with contract laws, taxes, drug uses, etc," wrote user Lapidariest.
"Think of each state as a country with their own particular quirks. Find the one most compatible with you and stay there," they advised.
If you were pulled over by a policeman, user bboe warned visitors to not get out of your car, unless they direct you to do so.
"Also, don't worry about getting your registration until the cop directs you," replied another.
Experience generosity during Thanksgiving
One American had clear advice for visitors, and that was to visit around one of their biggest holidays.
"Come to America just before Thanksgiving," wrote one person, "casually mention to American acquaintance that you're alone on Thanksgiving...Accept immediate invite to whatever Thanksgiving gathering is being held."
Another said that telling the person who had never celebrated Thanksgiving would "get you double invited."
Several non-Americans said they had experienced this, and similar offers around the Superbowl.
Visit a National Park
With more than 9,100 likes and 80 comments, one of the most popular suggestions was made by a user called AmIADelusionalArtist.
"GO TO NATIONAL PARKS," they wrote.
Dozens more people jumped in to add, yes you should visit the National Parks but also beware the animals.
"If you visit a National Park, don't mess with the wildlife. Buffalo (even cows) can kill you," one person commented.
Strangers on the street
If someone gives you a big smile while you're walking down the street, don't freak out, wrote user Legen--dary.
"No, you don't know them, this is just their way of being polite," they explained, adding that you simply need to smile back and then continue on your way.
Although, if you are casually asked "How's it going," by a passer-by, shop assistant or barista, they aren't looking for a literal answer, added one American.
"It's just a greeting. I went to college with a guy from Germany and this confused him quite a bit when he first got here. He thought people wanted to know about his whole day," they added.
Fortunately, if you don't love the disposition of the people around you, it can change markedly depending on where you are in America, wrote Drew_P_Nuts.
"In Louisiana, you have great conversations with folks at the bar. In South Carolina, I might invite you over to their house. In New York City, they're going to ignore you. In California, they're only interested if it benefits them," they wrote.
Other unusual quirks
The thread was also full of short but helpful pieces of advice.
"Don't just get BBQ once in one place. Go to all the places and get all the BBQ everywhere." —u/ Brancher.
"Tax is added to the shelf prices at the checkout."
—u/AlColbert
"Never accept something from someone on a street. The CD is not free."
—u/Portland-to-Vt
"In 98% of areas you go to, you'll need a car. The 2% where you won't are NYC, Boston, Chicago, and DC."
—u/ConnieLingus24
"Our 24-hour diners are legendary."
—u/Revolutionary-Tree18
"Food portions are huge, but anything you can't finish can be packed up for later. You just need to ask."
—u/FlygonsGonnaFly
"Always get health insurance unless you wish to be bankrupt. The US healthcare system is insanely expensive."
—u/Aggravating_Lemon_32
Any missing from the list? Let us know in the comments.
