Miami's road system is based along the numerical "Miami Grid" where Flagler Street forms the east-west baseline and Miami Avenue forms the north-south meridian. The corner of Flagler Street and Miami Avenue is in the middle of Downtown in front of the Downtown Macy's (formerly the Burdine's headquarters). The Miami grid is primarily numerical so that, for example, all street addresses north of Flagler Street and west of Miami Avenue have "NW" in their address. Because its point of origin is in Downtown, which is close to the coast, therefore, the "NW" and "SW" quadrants are much larger than the "SE" and "NE" quadrants. Many roads, especially major ones, are also named (e.g., Tamiami Trail/SW 8th St), although, with exceptions, the number is in more common usage among locals.
What is Miami's street plan called?
Miami Grid