View full lesson: http://ed.ted.com/lessons/how-the-konigsberg-bridge-problem-changed-mathematics-dan-van-der-vieren You’d have a hard time finding the medieval city Königsberg on any modern maps, but one particular quirk in its geography has made it one of the most famous cities in mathematics. Dan Van der Vieren explains how grappling with Königsberg’s puzzling seven bridges led famous mathematician Leonhard Euler to invent a new field of mathematics. Lesson by Dan Van der Vieren, animation by Artrake Studio.