The resulting reservoir, the northernmost of the New York City system, is located 36 miles (58 km) southwest of Albany and roughly 110 miles (180 km) northwest of New York City. It lies at the southern end of Schoharie County, the northeastern end of Delaware County, and at the northwestern end of Greene County. It neighbors such towns as Gilboa, Prattsville, and Conesville. It is an impounded portion of the Schoharie Creek, a tributary of the Mohawk River, itself a tributary of the Hudson River.