The fort Benedict Arnold attempted to surrender to the British in 1780 was West Point.
West Point was a strategically vital American fortification on the Hudson River in New York. Its position helped control the river corridor and protect communications between New England and the other American states. George Washington trusted Arnold enough to give him command of the post in July 1780, despite Arnold’s growing resentment over disputes about rank, expenses, and recognition.
Arnold secretly negotiated with British Major John André to hand over West Point. He supplied information about the fort’s defenses and proposed terms under which the British could seize it. The plot collapsed in September 1780 when American militiamen captured André while he was carrying documents connected to the scheme. Arnold learned that André had been arrested and escaped to the British lines before American authorities could seize him.
The fort itself was never surrendered. André was later hanged as a spy, while Arnold received a British commission and fought against his former country. This failed plot transformed Benedict Arnold’s name into a lasting symbol of treason. The other options were real Revolutionary War forts, but none was the target of Arnold’s 1780 betrayal.