Germany is renowned for Autobahns without speed limit and fast cars. Most people living outside Germany cannot imagine driving at unrestricted speed, but have seen photos of massive pile-ups. There is a touch of myth in both.
First of all, Germany does not have the highest level of highway fatalities in Europe. Despite the number of spectacular crashes, the statistics prove Germans to be better-than-average drivers. This has something to do with strict driver education requirements, (fabled) German discipline, good roads, and safe cars. It is also aided by the truth behind the other semi-myth.
It is true that large stretches of the Autobahn network do not have a speed limit. As with every aspect of German life, everything is permitted that is not specifically not allowed. (There are a lot of rules regulating human behavior.) Back to the Autobahns: many stretches do have speed limits, but there are enough kilometers to allow fun, speed, and recklessness.
In reality, there are three speeds on German Autobahns: ridiculously fast, standard traffic, and parked.
I have owned Porsches, Mercedes, and BMWs. This is not bragging, because these are standard cars in this country. Most taxis are Mercedes, and BMWs are rather middle class. That said, all are very fast. My preferred driving speed on the Autobahn is 180 kilometers per hour (about 112 miles per hour for fans of an English king's foot), which I found safe and swift enough. The biggest danger was other drivers, who had no comprehension of speed. A fast car on a good road was often a pleasure to drive, but it has become an increasingly rare pleasure.
The most common speed on Autobahns is 100 kilometers per hour (about 60), because of the increasing amount of cars on the road. Heavy, bumper-to-bumper traffic often moves at this speed. One is happy to be moving, but it can be frustrating on a highway without a speed limit. The days of open roads and cheap gas are long gone. German industrial prosperity has put automobiles into too many hands, but makes driving speeds similar to those of most countries.
The third speed, common during rush hour and vacation times, is required when traffic increases to fill the highways or there has been an accident. The Autobahn turns into a long, linear parking lot. Traffic jams have been known to extend up to 75 kilometers and take hours to dissipate. This is beyond frustrating, especially for anyone captured in a Porsche. News footage or photographs show people standing beside their cars staring at a packed Autobahn, surely dreaming of a different speed.
Autobahn driving in Germany is a case of "hope for the best and expect the worst"...