Let's ask it to a mathematician

Take a walk along the city yourself

Try to solve the problem yourself: Drag the red point over the city map in such a way that each of the seven bridges is crossed just once.
The people of Königsberg kept on trying, but they failed. The mayor of Danzig asked Leonard Euler to solve the problem. By the time the famous mathematician was living in Sint Petersburg and if someone was able to solve the problem, it must have been Euler.