The Piscataqua River is a 12 mile (19 km) long tidal estuary formed by the confluence of the Salmon Falls and Cochecho rivers. The drainage basin of the river is approximately 1,495 square miles, creating the third fastest-flowing navigable river in the world. It creates part of the boundary between Maine and New Hampshire, making its way into the Atlantic Ocean below Portsmouth.
Named by the area's original Abenaki inhabitants, "Piscataqua" combines "peske" (branch) with "tegwe" (a river with a strong current, possibly tidal). "Peske-tegwe", then, describes a place where a river separates into two or three parts, or literally, "a place where boats or canoes ascending the river together from its mouth were compelled to separate according to their several destinations"
The first known European to explore the river was Martin Pring in 1603. Captain John Smith placed a spelling similar to "Piscataqua" for the region on his map of 1614. The river was site of the first sawmill in the colonies in 1623, the same year the contemporary spelling "Piscataqua" was first recorded.
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