The main stream of the river is formed at 44°48′21″N 84°45′29″W in Frederic Township in Crawford County by the confluence of Kolke and Bradford Creeks, which both rise in Otsego County. The river flows south then turns east through Grayling, where it is joined by the East Branch Au Sable River at 44°39′55″N 84°42′13″W.

Where does the Ausable River flow?

The Ausable River (/ɔːˈseɪbəl/), also known as AuSable River and originally written as "Au Sable", runs in the U.S. state of New York, from the Adirondack Mountains and past the village of Lake Placid and Au Sable Forks to empty into Lake Champlain (at 44°33′40″N 73°25′25″WCoordinates: 44°33′40″N 73°25′25″W).

Which direction does the Ausable River flow?

The Au Sable River flows southward through the eastern part of the township, toward Grayling, while the Upper Manistee River flows southward through the western part of the township, then veers towards the southwest. Both Rivers are both known for excellent trout fishing.