There is this odd German custom....which actually fits into most city and state laws of Germany....which dictates that you will be quiet between the hours of noon and 3PM. Some areas have various differences on the quiet-time scheme....but it's basically two to three hours in the afternoon where you just can't make any real nose outside.
Examples? Mowing grass. Playing music. A party. Construction work.
Some towns run this between 2PM and 4PM.....some between noon and 2PM....so it's a bit different where ever you go.
Enforcement? This is the odd thing. If you are in the midst of a construction project....you might ask your carpenters to take a lunch period for an hour out of this, and then go back to work....hoping that some old geezer in the neighborhood doesn't call the cops. The cops reaction? They usually don't want to screw with you, and would prefer to give you just a warning, and walk away. You could violate the rule a hundred days out of the year, and the cops might never get sent out to ask questions.
My humble guess is that few if any tickets are ever given out in a normal year....for quiet-time violations.
Where'd this start? The best answer folks can state is that the older generation folks came to demand this....so they could nap in the afternoon. Political folks just kinda agreed, and it became a general law of sorts.
To be honest, there are a list of oddball laws like this: a ticketable offense if you run out of gas on the autobahn...for example. Or there's the general law of offending some guy by calling them an "asshole" and having to pay 20 Euro for the insult (your wife could even take you into court if you uttered the phrase at her). There's also that funny law about denying chimney-sweep guys access to your house, if he comes around asking for entry to check out your chimney (course, if you don't have a chimney, you can challenge the guy).
An American would be kinda curious over these odd situations and ask some stupid questions....mostly because we've never heard of such a rule. After a while....we'd have a laugh, and try to avoid getting into trouble. Note, I said we'd "try" to avoid getting into trouble. It's just that we are usually magnets for trouble.