DOWNTOWN — How many blocks are in Chicago?
It's a simple question, but an answer that's not so easy to find. When asked on Chicago-based Facebook pages, including Windy City Historians and Forgotten Chicago, responses included 12,000, 18,000, 25,600 and 32,200, among several others guesses.
Asked by DNAinfo to reveal an authentic answer, Peter Strazzabosco, the Deputy Commissioner for the Chicago Department of Planning and Development, provided one.
The city's mapping system identifies about 20,800 unique blocks in the city, Strazzabosco said.
"These are blocks surrounded typically by four streets in a rectangular pattern, but also possibly having different shapes and sizes depending on the development pattern of a given area," Strazzabosco said.
Strazzabosco said Chicago's arterial streets — for example Irving Park Road and Belmont Avenue — are generally a mile apart. Since most rectangular blocks are about 660 feet long, there are typically eight blocks between major arterials, though more are possible depending on how the blocks are oriented within the grid pattern. The short side of most rectangular blocks are about 330 feet, he said. The distances generally correspond to the center of the surrounding streets, not curb to curb.
Strazzabosco noted a number of diagonal streets sometimes change the shape of blocks into more of a triangle shape. Other manmade and natural features that can change block sizes and boundaries include highways, waterways like the Chicago River and railroad tracks.
"Of the 20,800 blocks, most are typically bordered by four streets in a grid pattern across the city," Strazzabosco said.
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