Formation

The first segment of the line was built in 1835 by the Portsmouth and Roanoke Railroad, which would be renamed the Seaboard and Roanoke Railroad. The Seaboard and Roanoke Railroad ran from Portsmouth to Weldon, North Carolina.

The line from Roanoke Rapids to Norlina opened in 1840 and was built by the Raleigh and Gaston Railroad. In 1852, the Raleigh and Gaston Railroad was extended from Roanoke Rapids east to Weldon. Its connection from Roanoke Rapids north to Gaston was permanently severed during the American Civil War.^[3][4] The extension to Weldon connected with the Seaboard and Roanoke Railway, essentially making a continuous line. The extension to Weldon also provided a connection with the Petersburg Railroad and the Wilmington and Weldon Railroad, both of which later became the main line of the Atlantic Coast Line Railroad.

In 1900, the Seaboard and Roanoke Railroad, Raleigh and Gaston Railroad, and other railroads were merged into a single company named the Seaboard Air Line Railway (later known as the Seaboard Air Line Railroad).^[5]

Seaboard Air Line years

Portsmouth Subdivision
Overview
Status	Still operating east of Garysburg, North Carolina under CSX
Owner	Seaboard Air Line Railroad
Termini	Portsmouth, Virginia Norlina, North Carolina
Technical
Line length	115.3 mi (185.6 km)
Track gauge	1,435 mm (4 ft 8+1⁄2 in) standard gauge
Electrification	No
Signalling	None

The Seaboard Air Line designated the line from Norlina to Portsmouth as the Portsmouth Subdivision (while the Raleigh and Gaston's track from Norlina to Raleigh, North Carolina became Seaboard's main line). The Seaboard operated passenger and freight service over the line. Though the 1950s, Seaboard ran a daily passenger train (which also carried mail) and a daily through freight train. A separate local freight train ran three days a week at the time.^[6]

Later years

In 1967, the SAL merged with its rival, the Atlantic Coast Line Railroad (ACL), whose main line crossed the Portsmouth Subdivision in Weldon. The merged company was named the Seaboard Coast Line Railroad (SCL). The line remained largely intact after the merger. However, SCL severed the bridge over the Roanoke River to consolidate the river crossings on the A Line's parallel bridge (the ex-ACL main line) effectively truncating the Portsmouth Subdivision to its current terminus in Garysburg. Ruins of the Portsmouth Subdivision's bridge over the river are still standing next to US 301 in Weldon.^[7] The remaining track from Weldon to Norlina was then redesignated as the Roanoke Rapids Subdivision.^[8]

In 1980, the Seaboard Coast Line's parent company merged with the Chessie System, creating the CSX Corporation. The CSX Corporation initially operated the Chessie and Seaboard Systems separately until 1986, when they were merged into CSX Transportation, who continues to operate today.