|Quoting DAL767400ER (Reply 20):|
Most of the parts near Hamburg are 100km/h, despite there being relatively few traffic, and an Autobahn in excellent condition.
One guy from Hamburg sued the authorities because of the speed limits, maybe Germany is the only country in the world where you can sue your state because of speed limits...
He lost, but the case went up to the highest court, and the court ruled that general speed limits on the Autobahn are illegal, there must be important reasons for them, such as lots of accidents on the limited part, road quality, extreme noise issues (a general speed limit because of noise is illegal!) compared to the rest. If other measures which are less limiting promise the same result (like forbidding trucks to overtake), those must be chosen instead.
In Hamburg, the authorities could argument that there were enough reasons for speed limits, because there was lots of traffic, especially when there were holidays. Since people came from many countries (Scandinavia, Germany), holiday periods were different from country to country, so setting a general limit was found to be less confusing than setting a flexible limit.
The courts really wrote several pages analysing why the speed limit was justified.
So everytime you see a speed limit you think is rediculous, you might be able to sue the government! There are examples where speed limits were removed after it was proven that they were not effective.
The homepage of the guy who complained, including the judgements: