The St. Lawrence and Atlantic Railroad (AAR reporting mark: SLA) is a shortline railroad operating between Portland, Maine and the Canada-U.S. border at Norton, Vermont and is owned by shortline operator Genesee Wyoming Corporation.

SLA has a Canadian counterpart to which it connects with at Norton, named St. Lawrence and Atlantic Railroad (Québec), which operates the line through to Montreal, Quebec.

Major communities served along the entire system include:

• Portland, Maine
• Lewiston, Maine
• Berlin, New Hampshire
• Island Pond, Vermont
• Sherbrooke, Quebec
• Montreal, Quebec

History

The SLA/SLQ line is formed from two historic lines, the St. Lawrence and Atlantic Railway and the Atlantic and St. Lawrence Railroad. These lines were absorbed by the Grand Trunk Railway (GTR) in the 1850s and formed part of the GTR mainline between Portland-Montreal-Toronto-Chicago until GTR was nationalized by the Canadian federal government under the Canadian National Railways in the early 1920s following GTR's bankruptcy. Traffic declined as the Portland-Montreal line became a secondary mainline in the CNR system and following railroad industry deregulation in the U.S. during the 1980s, CN (acronym/name change post 1960) decided to divest its Berlin Subdivision between Island Pond and Portland (what would become the SLA) in 1989) but still operated from Montreal to Island Pond. In the early 1990s, the latter section was divested to a subsidiary of SLA (what would become the SLQ).