|Maintained by FDOT|
|Length||3.603 mi (5.798 km)|
|West end||near St. Augustine|
|East end||/ in St. Augustine|
State Road 312 (SR 312) is a 3.6-mile-long (5.8 km) state highway serving St. Augustine, Florida in the United States. Its western terminus is at SR 207, and its eastern terminus is at SR A1A near St. Augustine Beach.
State Road 312 begins at the intersection between SR 207 and SR 312, where SR 207 continues northeast into central St. Augustine. About 0.4 mile east of the western terminus, SR 312 passes over the Florida East Coast Railway main line via an overpass. A mile from the western terminus, SR 312 intersects US 1, with SR 312 continuing a few blocks east through St. Augustine until a crossing with the Intracoastal Waterway. At the waterway, SR 312 enters St. Augustine city limits, where it terminates at SR A1A.
The entire route is in St. Johns County.
|0.801||1.289||Old Moultrie Road (CR 5A)|
|1.009||1.624||(Ponce de Leon Boulevard / SR 5) - St. Augustine, Bunnell|
|Bridge over Matanzas River (Atlantic Intracoastal Waterway)|
|3.603||5.798||/ A1A Beach Boulevard (CR A1A south - St. Augustine Beach, St. Augustine Amphitheatre||Eastern signed terminus; northern terminus of unsigned CR A1A|
|3.836||6.173||East end of state maintenance|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi