During the covid crisis, in January 2021, the German government decided to pass a law that prohibited people to leave their homes in a "15km radius around their hometown". The SDP (Social Democratic Party) introduced an app that showed a map with a radius around one's location, suggesting that that was the final moving perimeter ... The actual law never specified anything other than one's hometown which is synonymous with the town's border.
This app visualizes the actual space in which you were "legally" able to navigate based on the hometown's border.
The law was withdrawn shortly after because it was unconstitutional ...