Premise: The Salmon Falls River is a tributary of the Piscataqua River in the U.S. states of Maine and New Hampshire. It rises at Great East Lake, Newichawannock Canal, and Horn Pond and flows south-southeast for approximately 38 mi , forming the border between York County, Maine, and Strafford County, New Hampshire.
Hypothesis: The Piscataqua River is the largest in New Hampshire.