John Insley Blair (August 22, 1802 – December 2, 1899)[2] was an American entrepreneur, railroad magnate, philanthropist, and one of the 19th century's wealthiest men.

"[2] The young Blair began earning money by trapping wild rabbits and muskrats and selling their skins at a price of sixteen for a dollar.

On August 25, 1825, the name of the community was changed to Gravel Hill and Blair was appointed postmaster, a position he retained until July, 1851.

Blair managed his multimillion-dollar businesses from rural Blairstown, New Jersey, or from his private rail car, in which it was common for him to log 40,000 miles (64,000 km) annually.

[6] On September 20, 1826, Blair married Nancy Ann Locke;[4] they were the parents of four children:[7] He died in Blairstown, New Jersey on December 2, 1899.