Former state roads in southern Florida

In the mid 1970s, the Florida Department of Transportation (formerly the Florida State Roads Department) started a sequence of events that eventually resulted in the transferral of hundred of miles of roadway from State of Florida maintenance to county control. The first step was the addition of an S- or C- prefix onto the original FDOT designation (“S” represented “secondary”; “C” represented “county”). State Road signs started disappearing from the “C” roads and were replaced by blue pentagonal County Road signs in the early 1980s; the transition of “S” roads to county control took a bit longer (some State Road signs with S-prefixes remain standing two decades after the transfer to county control).

While the transition occurred throughout the State of Florida, the area most dramatically affected by this process was Florida south of SR 70 (which runs from Bradenton to Fort Pierce). While other State Roads had portions turned into county control (for example, SR 29, SR 31, SR 78, SR 707, SR 780, SR 880, SR 884, and SR 951), entire State Roads in southern Florida disappeared from the FDOT lists (although in many cases, local officials still refer to them as "State Roads"):

A few cases (like SR 731, SR 850, SR 858, SR 869, and SR 886), the former designation was subsequently reapplied to a different road in a different part of Florida.