Florida State Highway System
| State Highway System | |
|---|---|
  
Standard route markers in Florida
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| System information | |
| Notes: | State Roads are generally state-maintained. |
| Highway names | |
| Interstates: | Interstate X (I-X) |
| US Highways: | U.S. Highway X (US X) |
| State: | State Road X (SR X) |
| System links | |
The State Highway System of the U.S. state of Florida comprises the roads maintained by the Florida Department of Transportation (FDOT) or a toll authority. The components are referred to officially as state roads, abbreviated SR.
State Roads are always numbered; in general, the numbers follow a grid. Odd numbered roads run north-south, and even numbered roads run east-west. One- and two-digit numbers run in order from 2 in the north to 94 in the south, and A1A (formerly 1) in the east to 97 in the west (99 used to exist but is now a county road). The major cross-state roads end in 0 and 5.
Most routes of the form X00 are major diagonal routes; an even first digit indicates a southwest-to-northeast direction, and an odd first digit indicates a northwest-to-southeast direction.
Other three-digit numbers are placed in horizontal bands based on the first digit:
Three-digit numbers increase from east to west across the band; 30 is skipped because it runs along the Gulf Coast in the panhandle and doesn't go all the way across the state.
When the grid was first laid out in 1945, the rules were almost perfectly followed. However, over the years, as routes have been added, there has not always been room to follow the grid. Placements such as 112 (in the 8 band), 752 (in the 2 band), and 602 (in the 1 band) are the most notable violations of the grid system. The Pensacola area has a collection of these "misplaced" street numbers. When FDOT added route numbers to a collection of Miami-Dade County streets in 1980, most of them received 9## designations regardless of the band that they occupied.
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