It was one of the oldest such companies in the United States, and has owned railroads continuously since its founding in 1938.

[1] In August 2023, Macquarie Infrastructure Partners reached an agreement with Pinsly to acquire the railroad through its subsidiary Gulf & Atlantic Railways.

[2] Born in Cambridge, Massachusetts in 1899, Samuel M. Pinsly received degrees in engineering and law from Northwestern University before briefly serving in the U.S. Army during World War I. Pinsly founded his shortline operating company in 1938 with the purchase of the Hoosac Tunnel and Wilmington Railroad from his father-in-law, fellow shortline operator H.E.

[1] He was succeeded by Marjorie "Maggie" Silver, one of the first women to own a railroad company in the United States.

[4] Pinsly's business development manager stated in 2022 that the company sold off its other subsidiaries to focus exclusively on the Pioneer Valley Railroad.