What are the interesting culture shocks that you have experienced visiting different countries?

USA: Everything is so big. The roads, the cars, the malls, the carts, the cities, really everything. Even the people are big.

I live in Switzerland, a small country (about the size of the whole Los Angeles and San Diego area). Whenever I drive on a busy narrow single-lane road with oncoming traffic with manual transmission I am sure most US citizens are unable to cope. Like this (see Google Maps).

1. Papua New Guinea - the high level of personal security awareness. In our golf course in Port Moresby we had guards armed with Bow/Arrows, and Machetes. One tee box near the perimeter was famous for armed hold ups, so it was common practice for one player to hit his drive while the others kept a watch out for Raskols (the name for criminals). It is a beautiful country, which time forgot but plagued by this issue which affects your lives.

2. United Arab Emirates (UAE) - aggressive driving and tail gating by the locals. It is sort of unnerving when there is a high performance car/SUV driving at 120 KMPH, two feet from your bumper flashing their lights. When they cruise by you often see a leg stuck up on the dashboard which is a style of chilling while driving.

3. Sri Lanka - 1) During the civil war with the LTTE (Tamil Tigers), it was a high security atmosphere in the capital city of Colombo. One day my family heard an explosion in the house next door, in fact the room adjoining the room they were in. This had a common wall with the neighbors house. We later learnt that one of the staff there was playing around with a grenade which went off, and I dont need to say what happened to him. Apparently the driver (was an army deserter) had given him the grenade!
2)The other unusual experience was regarding golf in the summer, when the temperature is 40 degrees centigrade in the shade (104 deg Fahrenheit). One of my playing partners settled down for a drink after a scorching round which finished at 1 pm. He orders whiskey which was an unusual choice and then had a couple more. This was not uncommon.

Singapore - it is common for most applications (for anything including rental ads) to ask about your race, your job, your age and sometimes your income. A taxi driver might ask how much your income is when he drops you off at a nice condominium or house. He could follow that up with a question on how much rent you pay.

South Korea - 1) when I invited some 25 colleagues who were in my team to my house for dinner it was quite a shock to them. Some said to me later that this was the first time in 20+ years that any of their managers had ever invited them to their home for a meal (which is quite normal in Indian culture). Its the norm to do all business entertainment in restaurants. Many of them took a tour of the house and some even looked into the cupboards!
2) In a night when you go out for a couple of drinks with your colleagues (read this as the team), then there is a designated junior staff whose job it is to make sure that the boss returns home safely.
3) Weddings, promotions and funerals are expensive for attendees. For weddings and funerals - you are expected to give a gift of money, and the amount depends on your stature. If you are promoted you are expected to take the entire team (and your boss) for a night out of drinking the same day. This can be quite expensive for junior staff.
4) Sometimes staff come to office after a full night of partying (for say a promotion celebration) without going home. Needless to say it isnt a  productive day.
5) Despite the above dont mistake their work ethic. They have a very strong work ethic and ability to do amazing things. Probably the best in all the countries I have worked in.
There is much more but I wont go on about Korea.

Indonesia - Jakarta is an amazing sprawl which hits you, and you notice the absence of green spaces. The traffic is notorious and you learn to plan your life based on the place and time - you can spend hours just to travel a short distance. In the CBD area during peak hours, cars with 4 people or more are allowed to move on the main road. To bypass the law you can pick up "jockeys" which are often a young mother and a baby who hop into your car for a small fee of 5-6000 rupiah. They get off at your destination and then work their way back.

Vietnam - 1) Quite common to see cut fish (fillets), fresh chicken, beef and lamb being sold on the roadside on the pavement. Its a bit disconcerting until you get used to it. Worth mentioning that every morning the streets (and pavements) in certain areas come alive with pop up shops on the pavements. From fresh vegetables, fruit and meat. Why buy from a super market when you can get it fresh?
2) Takes a while to figure out how to cross the road on a busy street which is teeming with motorcycles and cars. You need to be bold, start crossing when there is a gap, and move confidently while making eye contact. If the traffic knows where you are heading they just go around you!

Turkey - There arent many places in the world (though Jakarta and Mumbai qualify) where your drive to and from the airport can be longer than your flight.

There is much to write about India but as an Indian I thought it better for others to cover that space.
China: the hockering and spitting. It's all I think about when I think of China. One week was not REMOTELY enough to get over the culture shock, and that's all the time I had there. For that reason, I cannot fathom ever going back. Oh, that, and the refusal to stand in line. It was a mob scene of shoving and pushing to be the first to: put your purse through the metro's security X-ray AND the first to remove it; the first to get a ticket on the metro, etc. And oh God: the madness of getting on the damned train. I was at the start of a train line, and as soon as the doors opened, people RAN to get on. Except these 2 guys who were in front of me: they just stood there. The train wasn't even 1/2 full yet. I was confused. A guy behind me looked at them, then the train, shrugged, and got on the train. I did the same. It wasn't until I was on that I realized, they were waiting to be first on the next train.

Chile: The food was INCREDIBLY dull, boring, and the people have an absolute aversion to spice. I was waiting for people to say, "Oh, God bell pepper!? No, that's too spicy!" The cream cheese in sushi and spring rolls. The TINIEST limes that have as much juice as a prune, which are used to make the national drink, the pisco sour.

Peru: honestly, I know this is a thing in a lot of the world, but the complete disregard for traffic signals. I was nearly hit by a car 3 times in Cusco when I was crossing the street after waiting for the light to change. I had the green, but cars just zoomed on through, not concerned about the traffic light, nor that there was a person crossing the street. Honestly, in a lot of the developing world, there's still a lot of disregard for laws, especially those that don't have more severe punishments.

Shortest reverse culture shock ever: I had returned to the US from 2 weeks in France, and I could not BELIEVE how LOUDLY people talk here. I had a permanent headache. At the office, when I would see my office mate I would BEG her to stop yelling, we were inside and it was quiet. 

Practically every time I come back from abroad, I am struck with how ridiculously loudly everyone in the US talks. And how CONSTANTLY! In Paris, people on the trains talked very quietly, if at all. This was around 5 years ago, so maybe it has changed, but when a Frenchman's cell phone rang, he'd walk off the sidewalk, and either sit down or talk quietly against a wall to take the call. In the US, it's a constant stream of each person holding full-on conversations on their phones, on the train, the bus, everywhere.
Here's a short list of memorable culture shocks:

India: the bobblehead.

Nepal: being airborne in my seat once every 10 minutes on an overnight bus ride from Karkarvitta to Kathmandu.

Jamaica: the poverty. Mostly jarring because it's in such close proximity to the U.S. Plus, the pictures we see are all crystal clear waters on white sand beaches.

Poland, Japan, and Iceland: the quiet. It's a bit eerie.

Thailand: pervasiveness of prostitution and elective surgery clinics.

China: laminated pamphlets in the hotel rooms about prostitutes and safe sex. Brothel inside the hotel. Offered to males looking into spa services even when accompanied by females.

Western Europe: it's truly like going back in time - the smaller towns are even more amazing - Ghent, Carcassonne,  Basque Region, and of course the high priestesses, Rome and Athens.

Maldives: ultra-conservative. My first time in a completely Muslim country. Women really don't engage with foreigners like they do in other countries. Even close female friends of people we stayed with only introduced themselves once and we were there for almost a month. Have lots of friends there, but they're all men.

And last one for now:

Mexico: I was totally shocked the first time I went and little girls and boys were covered in dirt trying to sell chicle for five cents and begging for water. I was horrified. There was clean water and I'm sure this kid could have gotten a shower not more than five miles away where our car was parked. I saw dozens of them that day. The problem already seemed too big. I was 18.

USA : 1) The most surprising thing was .. they have locks on trial/changing rooms in clothing stores. I mean its very weird every time I want to try a shirt / jeans I have to ask a person to unlock it... that person will have few keys and unlock one of them & after we are done .. lock it again.. infact some stores had self locking doors.

I never really understood how these trial rooms can be misused that they need to be locked. Strange.

2) Extremely courteous ppl .... everyone will greet you(complete strangers too!!) whenever they pass you (at least on tourist places).

3) They ALWAYS have exact change to the very last penny.

4) Quite clean country except White house gardens where it was filled with garbage just lying around.

China : You will find hot water almost everywhere. We were near north korean border in middle of night and our driver decides to take a nap!!! We visited the provisions store and even it had hot water machine. Basically instant noodle culture is a rage in China... so they have hot water everywhere.. you just go with ur noodle box , pour hot water from the water "cooler" and you have a meal ... so ppl carry instant noodle packs and eat whenever they want.

Their was a young man who had the opportunity to become an exchange student in the middle 60s. He was to spend a year in Southern India. So sorry trouble in paradise. No student visas. It was good his advisor had a backup. It was to spend that year on a kibbutz in Israel.

Icelandic Airways... Had to stuff paper matches into the sides of windows to stop it from rattling.

Luxenberg..I can't fit my duffel bag in that small car.

The Orient Express was an eye opener as we passed through the Check Republic... food through the windows. "My change"  as we abruptly pulled away.

The beer  gardens of Germany. The music , gayety , the size of beer steins.

Istanbul..The Gulhani hotel. Sitting next to diesel heaters and drinking chi. Sharing spots with travelers going in all directions. The toilet serving the entire floor were two bricks over a hole. Stand, squat and hope you don't slip..OH! the hash has to be recalled.

Getting off the plane in Israel and being hit with the overwhelming smell of orange blossoms.  Being met by a beautiful military women who pushed our bags INTO SECURITY.. WOW!!

Buying two  bikes and  riding them toward Hafi. The road goes up. A night sleeping in orange groves. Butts like chimpanzees upon arrival.

Looking for the bus station. Instead finding an idling TANK. Being asked if we had weapons. "Just this pocket knife". Why is the guy in the turret laughing? Why the tank?

Waking on the bus to find it full of chickens : and soldiers of all genders fully armed. WOW!! 

Expecting the bus to drop off the road as we traveled up. Being left on the road side with sand blowing . Seeing the flapping of a shack roof. Alongside a motor cycle  with a side car and machine gun. What  the F is going on?

Child you should have read the papers. Listened to the news.  The 6 day war was two weeks old. Tanks, cars, houses, people displaced, uniforms, boots, guns etc along every curve as we traveled further up into the  Golan Heights to Kibbutz Sasa.   So many more firsts.

Two years later. Returning with a new appreciation for my home and friends.
What was former German Kaiser Wilhelm's opinion of Hitler and the Nazis?

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For you personally : What is the biggest mystery about life?

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What are the top tips for travelers who are visiting Paris?

Top tip I always give is go on a river cruise on the Seine! It's the best way to see Paris. It saves you time and energy, and not to mention gives you unique perspectives of the city. If you're in Paris for a fixed amount of time, this is what I'd recommend.