Kaliningrad is a Russian enclave, surrounded by Poland and Lituania. [br]Let's go back in 1735. Königsberg is a Prussian ciry and it's a habbit to take a Sunday walk through the town, crossing the bridges on the river Pregel.

Seven bridges connect the two banks and two islands. As a game the question is raised: "Is it possible to make a walk through the town, crossing each bridge once?"