Twice a month a mail carrier on horseback traversed the South Country Road on Long Island. In winter the roads were, of course, impassable. Historians tell us that the service did not flourish and was withdrawn before the Revolution. There is a story that during the Revolution and for some years afterwards, an old Scot named Dunbar was in the habit of riding a voluntary post between the city of New York along the south road to Babylon and from thence a few miles o the east and then across the Island, to Brookhaven. He brought mail and newspapers to the inhabitants once or twice a month depending on the state of the weather. It was not until the beginning of the nineteenth century that there was a Post Office on Long Island. People had heir mail brought from New York or Connecticut by trading vessels.
On November 26, 1889, a Post Office was established in Great River.