Chicago

city · earth

A city on the south-western shore of Lake Michigan, laid out on a rectangular grid across an almost perfectly flat lake plain, with a lakefront reserved as public parkland by nineteenth-century ordinance. Both facts serve the marathon: the grid allows a course with very few turns, and the parkland gives a start and finish in the same place. The flatness is not marginal — the elevation range across the whole course is on the order of tens of feet — and it is the physical reason Chicago competes with Berlin as the fastest big-city marathon in the world. It is a canonical city object and is not defined by the marathon.