Kaliningrad, Russia

Kaliningrad is the westernmost regional capital of Russia, sitting along the Pregolya River with roughly 500,000 residents, located about 1,200 kilometers west of Moscow and 350 kilometers east of Berlin. Founded in 1255 by the Teutonic Knights as Königsberg, the city was renamed in 1946 after Soviet President Mikhail Kalinin. The 1333 Königsberg Cathedral on Kant Island holds the tomb of philosopher Immanuel Kant at its north wall, and the city was the birthplace of both Kant and Hannah Arendt. Its historic seven bridges inspired Euler's 1736 solution that founded graph theory, while the 28-storey House of Soviets, begun in 1968, still stands unfinished.