Located in the city of Dunedin, in southern New Zealand, the Baldwin Street has earned the distinction of being the steepest street in the world. This 350 meters long street begins with a moderate slope and then climbs steeply to reach a maximum slope of 1:2.86 or 19 degrees. In other words, the street rises by 1 meter for every 2.86 meters travelled horizontally. The street is so steep that it's surface had to be laid with concrete instead of asphalt otherwise on a warm day the tar would flow down the slope!
Baldwin Street is located in the residential suburb of North East Valley, running east from the valley of the Lindsay Creek up the side of Signal Hill towards Opoho. It rises about 70 meters along its length generating an average slope of slightly more than 1:5. Its lower reaches are only moderately steep, and the surface is asphalt, but the upper reaches are far steeper, and surfaced in concrete.
The street’s unusual steepness was the result of poor planning. Planners in London, who had no idea of the city’s topography, had laid out the streets in a grid pattern with no consideration for the terrain. This resulted in a number of streets that landed right on extremely steep hills. Instead of returning back to the drawing board, or at least, incorporating switchbacks to tame the slope, the roads were simply built at a staggeringly steep grade. Indeed, some of the streets the city planners intended were so steep that were unable to be laid.
Baldwin street ended up becoming the steepest. Other streets running parallel to Baldwin are all quite steep: Arnold Street (1:3.6), Dalmeny Street (1:3.7), and Calder Avenue (1:5.4).
Today, Dunedin residents take pride of Baldwin’s reputation. Every summer a number of charity events and races are organized on the street, including running from the base of the street to the top and back down again, releasing thousands of spherical chocolate-coated confectioneries from the top or sending thousands of tennis balls down the street.
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