Main Line (Seaboard Air Line Railroad)

The Seaboard Air Line Railroad’s Main Line was the backbone of the Seaboard Air Line Railroad's network in the southeastern United States. The main line ran from Richmond, Virginia to Tampa, Florida, a distance of over 800 miles. While some segments of the line have been abandoned as of 2025, most of the line is still in service and is owned by the Seaboard Air Line's successor, CSX Transportation as their S Line.

Route description

The Seaboard Air Line's main line began in Richmond, Virginia. From Richmond, it proceeded south to Petersburg before turning southwest through rural southern Virginia. It then entered North Carolina near Norlina and continued south through Raleigh, Sanford, and Hamlet. It then entered South Carolina just south of Hamlet and continued southwest to Columbia. Beyond Columbia, the main line turned south to Savannah, Georgia. From Savannah, it ran though coastal Georgia and entered Florida just south of Kingsland, Georgia. In Florida, it continued south to Jacksonville, where it turned west a short distance to Baldwin. From Baldwin, it continued south through Ocala, Wildwood, and Plant City to its terminus in Tampa.

For much of its history, the Seaboard Air Line divided its main line in to subdivisions on its employee timetables, a practice which is still used by successor CSX today. The Seaboard Air Line classified the main line as the following subdivisions:

• Richmond Subdivision (Richmond to Raleigh)
• Raleigh Subdivision (Raleigh to Hamlet)
• Hamlet Subdivision (Hamlet to Columbia)
• Columbia Subdivision (Columbia to Savannah)
• Orange Subdivision (within Savannah)
• Jacksonville Subdivision (Savannah to Jacksonville)
• Baldwin Subdivision (Jacksonville to Wildwood)
• Miami Subdivision (Wildwood to Coleman, which continued down a branch line to Miami)
• Tampa Subdivision (Coleman to Tampa, which continued via a branch line to St. Petersburg)

History

Creation

By the time the Seaboard Air Line Railroad (known as the Seaboard Air Line Railway before 1946) was officially created, track that would make up its main line had already been built by the company's predecessors. The main line was built in the late 1800s by the following companies:

By 1900, the Seaboard Air Line Railway was incorporated, which brought together the predecessor companies together and created the main line north of Camden, South Carolina. At this time, the company had leased the Florida Central and Peninsular Railroad (FC&P) network which expanded the system through Georgia and Florida. The Seaboard Air Line would fully not own the FC&P network until 1903.

Passenger and freight service

The Seaboard Air Line would run many historic passenger services over its main line, many of which ran from New York to Florida. Some of the Seaboard's passenger trains included the Florida and Metropolitan Limited, Atlanta Special, Suwanee River Special, Orange Blossom Special, Southern States Special, Cotton Blossom, Palmland, Silver Meteor, Silver Comet, Silver Star, Sunland, and Tidewater.

Seaboard also had a number of fast, high-priority freight trains called Red Ball freights between various points on its system. However, from 1918 to 1966, a number of through freight trains instead ran the Andrews and Charleston Subdivisions between Hamlet, North Carolina and Savannah, Georgia to allow passenger trains to be prioritized on the main line.

Improvements over the years

In 1909, the Seaboard Air Line established its own port facility in Tampa, Florida on an island just south of downtown. The island would be named Seddon Island, which was named after Seaboard's chief engineer W.L. Seddon. The main line was extended a short distance to the island via a drawbridge over Garrison Channel.

In the 1910s and 1920s, the Seaboard Air Line would make improvements to its network to allow for more capacity on the main line. In 1918, the company completed its East Carolina Line, which ran from the main line in Hamlet, North Carolina and ran through Charleston, South Carolina before reconnecting to the main line in Savannah, Georgia. The East Carolina Line would become the primary freight route through this area, which allowed passenger service to be prioritized on the main line.

In 1926, Automatic block signals were installed on the main line between Richmond and Hamlet and between Savannah and Jacksonville.

More improvements to the network were also made in Florida in response to the Florida land boom of the 1920s. In 1925, the Gross Cutoff in northern Florida was completed, which ran from a small turpentine village named Gross just south of the Florida/Georgia border and provided a direct route to the main line at Baldwin, bypassing the busy Jacksonville Terminal area. The same year, the company also completed its Brooksville Subdivision, which ran from Waldo to Tampa via Brooksville and Inverness which allowed for some freight trains to Tampa to be rerouted off the main line. By the end of the decade, automatic block signals were also installed from Baldwin to Coleman, and the main line was expanded to double track between Baldwin and Starke, between Wildwood and Coleman (where the newly-built Miami Subdivision diverged), and a segment near Tampa Union Station.

The Seaboard Air Line upgraded the signal system to Centralized traffic control along the full route of main line in the 1940s to improve efficiency. The Seaboard Air Line would also be the first railroad to install a talking hot box detector (the predecessor to the modern defect detector). This first talking hot box detector was installed on the main line in Riceboro, Georgia.

Mergers and consolidation

In 1967, the Seaboard Air Line merged with their long-time rival, the Atlantic Coast Line Railroad (ACL). The ACL also had a main line running from Richmond, Virginia to Tampa, Florida that was roughly parallel to the SAL’s main line. The two main lines crossed each other in Chester, Petersburg, Savannah, Jacksonville, and Plant City. After the merger was complete, the company was named the Seaboard Coast Line Railroad (SCL). To differentiate the two main lines, the Seaboard Coast Line designated the SAL’s main line as the "S Line" while the ACL’s main line became the "A Line". The letter S was added as a prefix to the mileposts on the S Line (S was also added to the beginning of the pre-existing letter prefixes on the SAL’s branch lines).

By the end of the 1960s, the Seaboard Coast Line would begin abandoning segments of the S Line in an effort to consolidate the combined network. In Virginia, the company abandoned the S Line from just south of Bellwood to Dunlop (just north of Petersburg). The remaining line at Dunlop was connected to the A Line, and a new stretch of track was built to connect the remaining track south of Bellwood to the A Line at Centralia. In southern Georgia near Savannah, the company abandoned the S Line's bridge crossing the Ogeechee River which was located directly beside the A Line. Remaining track on both sides of the river was then connected to the A Line, which had a double-track bridge over the river. This abandonment also eliminated the at-grade crossing of the two lines at Burroughs. By 1970, another short segment of the S Line was abandoned in Florida between Owensboro (near Dade City) and Zephyrhills.

In 1971, the Seaboard Coast Line abandoned more of the S Line in the vicinity of Petersburg, Virginia. Track was removed from the connection to the A Line at Dunlop though Petersburg to Burgess with service being consolidated on the A Line. The Burgess Cutoff was then built to connect the remaining S Line to the south to Collier Yard on the A Line. The S Line's tall bridge over the Appomattox River in Petersburg, which was built in 1913, eventually had its deck removed in 1983 leaving only its concrete supports.

In 1979, the Seaboard Coast Line closed its terminal on Seddon Island in Tampa and sold the property. The bridge to the island was removed and track was truncated to Old Tampa Yard, which was the primary freight yard for Tampa before the construction of Yeoman Yard in the 1950s. Seddon Island has since been redeveloped and is now known as Harbour Island.

In 1980, the Seaboard Coast Line's parent company, Seaboard Coast Line Industries (SCLI), merged with the Chessie System, creating CSX Corporation. CSX Corporation initially operated the Chessie and SCLI Systems separately, however in 1982 they began the process of consolidating the railroads of both holding companies. This began with the formation of the Seaboard System Railroad, which merged all of the railroads owned by SCLI into one. In 1986, Seaboard System renamed themselves CSX Transportation (CSXT), and by August 1987, the Chesapeake and Ohio Railway, the final remaining railroad under the Chessie System brand, was merged into CSXT. As the transition into CSX was being completed, the company would abandon more segments of the S Line. In 1986, CSX abandoned the S Line between Riceboro and Bladen, Georgia, severing the line as a through route between Savannah and Jacksonville. Additional track was abandoned between Bladen and Seals, Georgia four years later. In 1987, the S Line was abandoned between Collier Yard (south of Petersburg, Virginia) and Norlina, North Carolina. A short stretch of the S Line was also abandoned between Jacksonville and Panama Park in the 1980s.

Another short stretch of the S Line between Tampa Union Station and Gary was abandoned in the late 1980s after Amtrak discontinued service to St. Petersburg. Remaining track from Tampa Union Station to Old Tampa Yard was removed in 2023.

Current conditions and future plans

As of 2025, much of the line is still in service.

At the north end, CSX still operates the line from Richmond to just north of Chester, which is now CSX's Bellwood Subdivision.

In Petersburg, Virginia, the concrete supports that once held the S Line's bridge over the Appomattox River are still standing on the northwest side of Petersburg. Despite abandoment of the S Line between Chester and Norlina, North Carolina in the 1980s, CSX continued to own the right of way of the route up until 2019, when it was sold the right of way to the states of Virginia and North Carolina. The states are doing preliminary work to rebuild the line for high-speed passenger service as part of the Southeast High Speed Rail Corridor. Virginia has since bought its portion of the line, and, as December 2023, North Carolina is negotiating a deal to buy the portion in their state.

Further south, the S Line is still in service from Norlina, North Carolina to Savannah, Georgia. This segment is now CSX's Norlina Subdivision, Aberdeen Subdivision, Hamlet Subdivision, Columbia Subdivision, and Savannah Subdivision. Amtrak still operates on this segment from Raleigh to Savannah. This is the only segment of the S Line that still carries regular passenger service.

South of Savannah near Richmond Hill, the remnants of the S Line's former bridge over the Ogeechee River remain which are right beside the A Line bridge.

The shortline Riceboro Southern Railway now operates the remaining S Line between Richmond Hill and Riceboro, Georgia. Further south, the First Coast Railroad operates the remaining S Line from Seals, Georgia to Yulee, Florida. Both the First Coast Railroad and the Riceboro Southern Railway took over their respective sections of the S Line in the mid 2000s and are both owned by Genesee & Wyoming. South of Yulee to Panama Park near Jacksonville is now CSX's Kingsland Subdivision. The S Line Urban Greenway is now on the former right of way in northeast Jacksonville.

The S Line in Florida is CSX's primary freight route through the peninsula. From Jacksonville to Baldwin, the S Line runs through CSX's Jacksonville Terminal Subdivision and runs on the Wildwood Subdivision from Baldwin to Owensboro (where the Wildwood Subdivision continues south on a former ACL route). The Hardy Trail runs on part of the abandoned right of way near Dade City. From Zephyrhills to Gary in Tampa, the line is CSX's Yeoman Subdivision and part of the Tampa Terminal Subdivision.

Historic stations