Driving Tips

In Germany for sure, only use the inside (left lane) for passing, not cruising, when you have two lanes going the same direction.

Take a look at each country you will be driving in. Get familiar with the road signs and their rules. Also, the speed limits. In some places speed limits are not actually posted. You're just suppose to know the limits for various scenarios like motorways and built-up areas...

Check if International Driver's License is required in addition to your regular license by any of the countries and/or your rental agency.

Not understanding the rules will not get you out of a ticket and fines.

If this is your first time driving in these places, a GPS can be a very helpful tool. The GPS will help you to keep track of the continuously variable speed zones you will encounter. It will also be very helpful locating fuel stations and parking options.
Do study the signs before you drive. They are not the same as ours. And as has been noted, do not sit in the passing lane. If you are in the passing lane, be ready to move over. The closing speeds can be really hard to appreciate until you experience them.
If you don't like tickets, pay close attention to the signs.
WRT parking, I always try to plan ahead and book hotels, ABB's etc. that offer parking. You will probably have to pay for it, but having an option can be very useful. It is not fun to drive all day only to learn that your hotel is located somewhere that does not offer nearby parking.

Ensure you get vignettes at the border for any country that requires one, e.g., Austria, Switzerland.

Look up parking lots for villages, towns, and cities you know you will visit. Bookmark them in your navigation app and you can go right to them, saving you some time when you get to that time. Surprisingly, many towns and villages have free lots, but you need to know where they are beforehand since most are unmarked.

Lane discipline on autobahns or whatever they are called in other countries! Already mentioned but drive in right lane unless you need to overtake a slower vehicle, if there are 3 lanes you use lanes to the left in order depending on speed of traffic, you never overtake on the right. But pay attention if road signs before junctions have actually split the traffic flows and not all lanes are for the same direction.... Same rule across Europe except UK and Ireland where it is the other way around. And don't forget to use turn signals when you change lane (many cars will resist the stearing if you don't)

Also, go to Youtube and look up the process of Rettungsgasse (rescue lanes) which are the law in Germany and Austria ( and should be everywhere else). You will notice there are two types of video, the official / semi official instructional versions and those that abuse drivers who get it wrong! You don't want to be ridiculed on Youtube do you?

Also already mentioned, Austrian autobahn vignette https://www.asfinag.at/en/toll/vignette/ on autobahns and express roads. Note that the green bits have special tolls and the grey bits don't even need a vignette, there are two grey roads which are particularly used by tourists. The section on that map around Salzburg is basically the link between the German A8 and most Salzburg exits. Not on that map, there is also the B179 road in the north side of Tirol which links Fussen to Innsbruck, this is signposted as an express road thus banning tractors, mopeds etc but has vignette exemption signs as well.

Many areas have parking controlled by blue "clock" discs which you leave in the front windscreen, you normally set your arrival time and get a ticket if you stay too long. Check the glovebox of a rental to see if the car has one, might be in the handbook if they left it for you.

Fuel pumps are usually green for unleaded and black for diesel (a lot of rentals are diesel). With unleaded the E10 will be OK for most rentals unless they actually have a sticker saying E5 only (and those cars will cost a fortune to rent!).

Make sure that the insurance does cover all the countries.

And make sure they will let you take the car east, some companies have restrictions on going east due to theft.

If you enter central urban areas in main German cities like Frankfurt and Munich, you need to have a sticker certifying the pollution class of your car.

https://urbanaccessregulations.eu/countries-mainmenu-147/germany-mainmenu-61/munchen

You do need also stickers for Austrian, Czech and Hungarian highways, while Poland has a mixed toll system. All matters to inquire, country by country.

Unless there are important stop-off points between locations, you are better off using trains than driving.

Every country may have some individual nuances in traffic laws like who has the right of way at intersections. But you will study and know these. Find your parking now. Add up the cost and make sure the credit card can take it. Get a WISE account as that seems to be the easiest for paying fines when you get home. Get the most complete insurance coverage available.

International Driving Permit should be carried. There is no International driving license. The permit basically covers a translation of your local driving license. I(Don't ask me how it works). You will need your own state/country license and the IDP. Get it for about $20.00 at AAA, and you need a photo, usually available at AAA also.

Judy. Thanks for the correction-International Driver's Permit.

Confirm with the rental agency, you can take the car to your destinations.

Agree to this point. Some brands and car categories are not allowed to take to certain countries. Take this seriously.

Individual restrictions per rental car firm. Example Sixt with categorizing countries into 3 zones.

Ensure validity of foreign driving licenses and likely need for IDP in Germany.

Make yourself familiar with road signs (example Germany) and traffic rules per country, e. g. in Germany no turn on red except with green arrow sign or light.

There have been some very interesting and informative posts here; kudos to the posters for their insights.

I'm quite sure having a Wise account secures many benefits, but I don't have one and I've rented cars in Europe ten or more times. So it strikes me as a "nice to have" thing but not a necessary one. Don't get one solely in order to rent a car. The IDP, conversely, is a necessity for most places in Europe.

I didnt say to get Wise to rent a car, I said to pay the fines afterwards. Humor lost on many I guess. Its based on this: https://community.ricksteves.com/travel-forum/italy/ztl-violations Offered not so much to pay the fines as a suggestion that the best among drivers may end up with one and it can be a bit of trouble to deal with.

I think most reasonably experienced and cool-headed drivers from the US are fine with 99% of the driving they'll do in Europe. However, it is just "different" enough that it pays to do the pre-game work to be comfortable when you get there (like posting the question you do).

Some of the challenges I've faced over the years are things like:
- toll roads where I didn't quite know if they were worth it (time wise), how to pay, when they were expected, etc., but luckily, nowadays GPS and mapping apps are a bazillion times better and you can peruse the map and familiarize that info early.
- parking in big cities (usually a nightmare unless pre-located) and small towns (signage is "different" just as it can be across the US). I've street parked in some small town (or even medium cities like Nice) and literally walked the block trying to make sure I wasn't breaking one of the many rules for parking. A good tip is to also "drop a pin" for your parking location if your phone isn't doing that automatically. After hours touring, the "obvious" location you parked may have faded.
- rental car insurance - have that figured out before getting to the counter for the usual hard sell. Your own car insurance and the credit card will have detailed coverage, so know what that is and if it matches your expectations/needs. Also, before leaving with the car, inspect it and do the now normal full car video with your phone to capture the pre-departure state.
- As mentioned, a route that dips into somewhere like Switzerland - even for a short stretch of highway - can require a "tag" showing the road fee has been paid. It can catch you out.
- speed cameras (like the US) are real and in places that likely see lots of folks speeding. Slow down and stick with the posted speeds - it keeps those sneaky tickets from getting you and it gives you a chance to enjoy the drive.
- diesel(!) fumes in a Stau/traffic jam seems to be getting better, but man can that give me a headache. We're randomly sat in traffic all across Europe for an assortment of reasons, but almost all of those gridlocked situations featured the ever-present diesel exhaust. You can't avoid it, but at least modern GPS to reroute and the cleaner burning diesel vehicles has made it much better.
- gas stations are sometime (I stress SOMETIMES) hit or miss with their acceptance of US credit/debit cards. Sometimes you have to go inside to deal with a human to sort it out, but that's a challenge if refueling on a Sunday, holiday, late/early, etc. And KNOW WHAT FUEL your car takes. Diesel is now "quiet" and relatively stink free, so make sure you understand your vehicles fuel type AND what the locals call it. Their terminology for the US equivalent will vary.
- I did find driving in Germany and the Autobahn especially to be fun and "easy" as long as you're a person who pays attention when driving. Only pass in the passing lane and only pass when there are no cars approaching at a high speed from behind already. Pass and get back over. If, in the US, you check your rearview mirror a little, then get in the habit of checking it A LOT. A car in the distant horizon behind you can be right behind you in a surprisingly quick amount of time. Get used to that speed differential and plan passes accordingly.
- brush up on their signage. Again, it's similar, but just enough different to confuse. Cars are often prohibited in downtown areas but no physical barrier will be there - just a sign letting you know. Read the room to see if things look strange - ie no other cars or a change that sticks out - because you may have missed a sign and are now driving in a place meant only for delivery vehicles or the like.
- be ready for NARROW roads. If you're good with judging the vehicle's boundaries, you'll be fine, but if not, you'll be paranoid that you're gonna take off the mirrors or sideswipe building or parked cars.
- Finally, HAVE FUN!

Those driving in the UK would do well to read that nation's road rules before driving there. Some rules are quite different from what US drivers are accustomed to.