In the late 1880s, the Florida Central and Peninsular Railroad was expanding its system and decided to build their own line to Savannah, GA. Trackage rights had been sought over the Plant System's tracks but when that didn't work out they were forced to expand their own line to secure a connection to the north. The new line was begun in 1892 and was extended from a point north of Jacksonville (at a crossing then known as Hart's Road, today as Yulee, FL) to Savannah. Completed in 1893, this new route was 36 miles shorter than the Plant System's mainline and hugged the Georgia coastline. The Plant System was distraught over the completion of a competing new line in the marshes previously thought to be impassable!
Eventually, the FC&P was absorbed into the new Seaboard Air Line, while the Plant System became the Atlantic Coast Line. For the next 60 years, the SAL and the ACL were arch rivals — their parallel mainlines crossed each other's at no less than 75 locations. In the early 1950s, both the SAL and ACL announced they were undertaking a study of the possibility of merging the two systems, as considerable financial savings would be realized if the they merged. However, numerous problems and arguments kept the two railroads from merging until July 1, 1967, when the two became the Seaboard Coast Line.
At first, nothing changed on the "S" line. Previous merger talks in the 1960s recommended that the SAL route be considered the primary route between Savannah and Jacksonville, since it was 36 miles shorter than the ACL route. However, after the merger the SCL continued to operate both lines until the CSX merger in 1980. The "S" line had been proposed for abandonment in 1979 but it stayed in use through the Seaboard System era. By 1985, CSX had considered the "S" line as surplus trackage and with the many bridges to maintain the decision was made to retire part of the route from Riceboro to Thalmann. The last trains ran in October, 1985.
In early 1986, CSX began to remove the trackage south of Riceboro. A spur was left in place from Bladen to Thalmann to serve a wood yard but the line was shuttered in 1987. The route south of Bladen was redesignated the Kingsland Subdivision and CSX kept it open another 3 years. But in November of 1989 it too fell silent forever. The track came out in 1990 from Bladen to Seals, just north of Kingsland. CSX later regretted taking this section up but made no attempt to restore it. The major trestle at Woodbine was removed except for a small section that was converted into a fishing pier. The portion from Yulee to Kingsland is now operated as a shortline.
Many artifacts remain along the abandoned rail corridor, and most of the bridges still stand. There has been talk of converting the route into a hiking trail from Kinglsand to Riceboror, a total of about 80 miles of former SAL mainline.
Thanks to Eugene Cain for contributing information about this route.