Beaver River is a hamlet that is six-tenths of a mile square, at the east end of Stillwater Reservoir, in the town of Webb in Herkimer County, New York, United States.

The hamlet has a year-round population of eight that increases during the summer, as many people have camps in this wilderness area.

No roads lead to the hamlet; it is accessible only by hiking, small self-propelled private track speeder or boat in the summer and by snowmobile, snowshoes or cross country skis in the winter.

The last New York Central Railroad passenger train left Beaver River on April 24, 1965.

[1] Beaver River was created in 1892 by railroad builder Dr. William Seward Webb as a stop on his newly completed Adirondack and St. Lawrence Railway, which became the Mohawk and Malone Railway and ultimately, the New York Central.