Monument Circle as the city's address origin

Monument Circle (the Soldiers' and Sailors' Monument) serves as the zero point for Indianapolis's street-numbering system. The city's original 1821 plan by Alexander Ralston placed a circular plaza at the center and streets are designated N/S/E/W relative to the Circle. Addresses and block numbers downtown are measured outward from this central monument, a layout that is uncommon among U.S. cities.