Not hard at all! All of the major Autobahns are there, so you'll have no problem! No, roadsigns won't always be in English. Since you're coming from the US, I'd take a quick look at the European road signs. The ones that you really have to be aware of is who has the right of way on certain streets!
Correct!
In terms of saving money and convenience, yes you'll need a car.
Riding the train is expensive in Europe, especially if you don't want to ride regional lines which take forever! ICE is very expensive in Germany and depending on how long you're going you can expect at least a 50 EUR ticket, one way. Within the cities may be a bit more difficult with a car. If you can, try to get a rental with a navigation system. Many of those cities are filled with one way roads that can start to get very confusing. Either bring someone who can read a map very well and very quickly or get a rental with a Navi!
Hmmmm, IDK. Really depends on what you want to do
Cologne is very expensive and if you will be speaking German, get ready to ask "Wie?!" a lot since the Germans in Cologne speak funny, lol
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Be careful driving on the German autobahns. Typically there is no speed limit on there (unless there is a sign that says otherwise) and many people drive very fast. Here are some rules that Americans (including myself!) tend to forget:
- You can't pass on the right. I was a big fan of this when I lived in the states and I know a lot of Americans who live near me have made this mistake and have gotten tickets from the police.
- No right turns on reds. VERY VERY important! Even if nobody is coming, you're still not allowed to turn until the special right hand turn light comes on.
- When driving in cities, there is a special sign that says which road has the "Vorfahrt". You must abide by these signs and if you take somebody's "Vorfahrt" away, be prepared for a very angry German. Sorry, should have explained what vorfahrt is. Basically, it's the road that has priority over the others
I'm going to go look now for a website with the road signs just so you'll have an idea what they look like