Atlantic City is located on Absecon Island, a bit south of the Jersey Shore's midpoint. In 1850, the island was a land of sand dunes, with some cultivation by the descendants of Jeremiah Leeds who served in the Revolutionary War. A local Columbia-educated doctor, Jonathan Pitney, saw an opportunity to develop the land as a seaside "health" resort. Nobody else saw such an opportunity.
Realizing his limited means (rural doctors didn't earn much), Pitney formed an alliance with Samuel Richards, an industrial baron in the rural southern, central part of New Jersey. Richards used his clout to talk the politicians into cutting a railroad from Camden to Absecon Island. He could use it as a way to transport his factory goods into Camden, a large port city at the time, and Pitney could use it as a way to get passengers from Philadelphia and Camden to his planned health resort.