The Empire State Area Code
Zip codes were originally invented to help the postal service determine where your mail needed to go. Larger cities had more inhabitants than smaller cities (duh), so the USPS separated neighborhoods by postal codes. When this happened, so much mail was going to the Empire State Building that it needed its own zip code. It still uses it by the way, so if you want to mail something to the Empire State Building, you have to use the 10118 zip code.
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