The city of Karlsruhe, Germany was planned with a palace tower at its center, surrounded by 32 radiating streets. Because the design resembled the ribs of a folding fan, the city is sometimes called the “fan city” or “Fächerstadt.“ Additionally, this city’s urban plan gave rise to the geometry concept of “Karlsruhe Metric” which refers to a measure of distance that assumes travel is only possible along radial streets and along circular avenues around the center.