Erie Triangle

The Erie Triangle is a roughly 300-square-mile tract of American land that was the subject of several competing colonial-era claims and which was eventually acquired by the U.S. federal government and sold to Pennsylvania so that the state would have access to a freshwater port on Lake Erie. The Erie Triangle land makes up a large portion of present-day Erie County, Pennsylvania.
Most of northwestern Pennsylvania came under American control following the 1784 Treaty of Fort Stanwix with the Iroquois Confederacy. The following year, a boundary dispute between New York and Pennsylvania erupted. Following a surveying effort by Andrew Ellicott representing the Pennsylvanians and James Clinton and Simeon DeWitt representing the New Yorkers, the western edge of New York was set at 20 miles east of Pennsylvania's Presque Isle, a small peninsula off the coast of Erie, Pennsylvania. However, this left an unclaimed area, which came to be known as the Triangle Lands.

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