Fort Billingsport: Kosciuszko's Underwater Trap
Near Wilmington, New Jersey
In the autumn of seventeen seventy-seven, the fate of the American Revolution pivoted on who controlled a river. The British had captured Philadelphia in September. Washington's army was retreating north to Valley Forge. But the British army holding Philadelphia could not be fully supplied and reinforced until the Royal Navy controlled the Delaware River. Standing in their way was a system of underwater obstacles designed by a Polish engineer, and the small fort on the New Jersey shore built to defend it.
Fort Billingsport, near what is now Paulsboro, New Jersey, was one anchor of the river defense line. The obstacles themselves were called chevaux-de-frise, massive wooden frames weighted with stone and sunk to the river bottom, each studded with iron-tipped beams angled upward to just below the waterline. Any ship trying to sail through would strike those hidden spikes and tear its hull open. Tadeusz Kosciuszko, the Polish military engineer who had come to America to fight for independence, designed the fort's fortifications at George Washington's request, while the river obstacles were designed by Robert Smith.
On October second, seventeen seventy-seven, fifteen hundred British regulars attacked Fort Billingsport from land. The garrison, badly outnumbered, burned what they could and abandoned the fort to avoid capture. Five days later, British forces returned to begin the slow, dangerous work of pulling the chevaux-de-frise apart underwater. Within two weeks they had opened a gap wide enough to move HMS Roebuck through.
The river forts fell one by one over the next several weeks, a desperate rearguard action that cost the British time and blood even as it ultimately failed. The prolonged campaign gave Washington's army critical weeks to consolidate before the terrible winter ahead.
Today a small park marks the site of Fort Billingsport in Paulsboro. The chevaux-de-frise, parts of them still in the riverbed, stand as one of the Revolutionary War's most ingenious, and most forgotten, defensive gambles.
