We already know about the tipping culture, endless freeways and "Have a nice day!" services, but the first time visitor to the United States still has a few surprises in store. Some are gloriously welcome, others less so. Here's what to be prepared for …
Accessible National Parks
The National Parks Service is the shining beacon of all that is good about the US. Ranger guided tours and facilities and consistently excellent, while the information handed out for free is above and beyond the call of duty. Perhaps most surprisingly, though, you don't need to be a hardcore hiker to explore rugged, remote parks. The policy of putting in drive-up viewpoints and easy, flat paths makes the parks remarkably easy to travel round – even if you've limited mobility.
Chain motel quality
From TV and movies, you'd be forgiven for thinking that America's motels are full of used syringes and butchered hitch-hikers. But standards are surprisingly high. OK, the likes of Super 8, Red Roof Inn and La Quinta are rarely character-packed and exciting, but they're reliably, solidly decent.
These same chain hotels also tend to provide a perfunctory breakfast – usually cereals in a scratched Perspex container, bagels, cream cheese and grape jelly. They're also served on paper plates, with plastic cups and cutlery – all of which are simply thrown away afterwards. It is jaw-droppingly wasteful.
Truly global food
The Thai, Chinese and Italian can be taken as read, while Peruvian and Brazilian are properly starting to infiltrate globally. But the joy of dining in the US is surprising diaspora enclaves that introduce cuisine not regularly found elsewhere outside the homeland. So Miami has great Cuban and Haitian restaurants, Washington DC is superb for Salvadorian and Ethiopian, while New York has everything from Ghanaian to Puerto Rican.
Interchangeable tasteless cheese
Finding a meal that doesn't have cheese in it can be quite the task in the less cosmopolitan parts of the US. And while the country does have some great cheeses, anywhere offering a choice will usually have American, Swiss, provolone or Monterey Jack. They all share a nigh-on identical, nothing-y taste.
The US has the best craft beer scene in the world, but it tends to focus in pockets. About five years ago, most bars would still serve a selection of awful beer (Budweiser, Miller Lite etc). But this is changing. You'll have to go somewhere truly dreadful to not have at least one pretty good option – usually Sam Adams or Sierra Nevada, plus maybe a local brew or two.
Middle lane hogging quickly becomes a sanity preservation measure on freeways. Stick to the right or left lane, and it suddenly insists anyone in it has to turn into an unexpected exit ramp. If you can't get out in time, this can lead to an absurdly time-consuming diversion.
Changing lanes, alas, is easier said than done. American driving, on the whole, is admirably safe and un-hoonish. But the levels of alertness and courteousness are dismal. Most drivers are on internal autopilot, usually with cruise control switched on, and finding someone who'll let you out when trapped in the wrong lane is a frustrating rarity.
Turn right on red
The US has a pathological fear of roundabouts, leading to an endless stream of four way junctions. In a bid to stop traffic grinding to a halt, you're allowed to turn right on a red light if it's safe to do so, unless signs state otherwise. New York City is the one notable exception to this turn right on red rule.
Every other TV ad is for some sort of drug that will cure your arthritis/ incontinence/ bone disease/ weird cheesy toe condition, and they all finish with someone rattling off a list of terrifying-sounding side effects as quickly as possible.
…And lawyer advertising
While the drug ads monopolise TV, the enormous roadside billboard ads are filled with grinning, creepy faces of lawyers. Each one is weirdly specialist – whether it's motorbike accidents or terrifying side effects from the drugs advertised on TV – and has a phone number along the lines of 0800 PAY OUT 4U.
Ubiquitous valet parking
Many hotels and restaurants insist on cars being parked by valets – who will often change your seat settings, take 15 minutes to bring your car back when you need it and charge you handsomely for the dubious privilege.
Almost everything in the US is paid for by credit card. Laundry machines and parking meters are the panic-inducing exception. They need feeding quarters. Lots and lots of quarters. Which you probably won't have, because you've paid for everything by card.
Zip code obstacles
Most petrol stations have pay at pump facilities, but as you'll need to enter a zip code for security reasons, they're useless to anyone with a non-US credit card. Expect to have to go in and pre-pay.
There's a similar obstacle when buying New York Subway tickets – but few foreign visitors know that tapping in 99999 as a zipcode will work when using an overseas card.
Not including tax
Prices in the US are almost always quoted excluding tax (petrol stations being a notable exception). Annoyingly, price tags also won't state what percentage taxes are going to be added. Unless you've memorised the city, state and federal taxes on each type of product, expect to never know how much you're going to pay until it has been rung through the till.
Shower gel denial
American hotels have a bizarre antipathy towards shower gel. Even higher end hotels that merrily provide conditioner, moisturiser, shower caps and vanity kits will often just leave a bar of soap for showering with. Prepare to cart your own bottle around.
Nothing short of a legalised swindle, resort fees are automatically added to the bill in some hotels, rather than included in the advertised price while booking. These allegedly cover pool use, phone calls, WiFi etc, but it's basically a way of extracting an extra $15 - $40 a day. Florida, Las Vegas and Hawaii are notorious for it.
Tipping is a well-established minefield, but watch out for joints (usually in the same areas that charge resort fees) that automatically add a gratuity to your bill "for your convenience". This will always be at least 18%, and it's probably there because they heard your foreign accent. They'll usually take it off if requested, but often not without a whiney fight.
At least 70% of the time, whatever food you have ordered will come with a pickled gherkin on the side. This is irrespective of whether you asked for it or the menu states you'll get one.
College sport obsession
Elsewhere in the world, university sport is regarded as a low tier irrelevance. In the US, it's multi-million dollar stuff, with university stadiums regularly filled with 80,000 fans and support more fervent than major league teams attract. No, it doesn't make any sense; just run with it.
Have you visited the US? What surprised you on your visit? Post your comments below.