Previously, Staten Island and Long Island / (Brooklyn) were connected and the Hudson River emptied into the Atlantic Ocean through the Raritan River, taking then a more westerly course through parts of present-day northern New Jersey, along the eastern side of the Watchung Mountains ridge to the area around Bound Brook, New Jersey, and then on into the Atlantic via the Raritan Bay.

A build-up of water in the Upper New York Bay allowed the river to eventually break through to form current The Narrows less than 12,000 to 13,000 years ago as it exists today.

[1] The first recorded European entrance into The Narrows off the East Coast of North America, was in 1524 by the Italian Florentine explorer Giovanni da Verrazzano (1485–1528), who was in the employ of and sailing for the Kingdom of France and its monarch, King Francis I, who set anchor off-shore in the strait and was greeted by a group of Lenape natives, who paddled out to meet him onboard his new strange huge sailing vessel in the strait.

the Battle of Brooklyn) of August 27, 1776, before they made their escape, evacuating at night by barge / rowboats across the East River back to Manhattan, during the decisive New York and New Jersey campaign of the American Revolutionary War (1775–1783).

The Staten Island Tunnel, carrying the New York City Subway system line under and across The Narrows, was partially built during the 1920s but was never completed.