The west branch drains spruce forests of the southern part of the Maine North Woods, and drops 1,174 feet (358 m) to Medway from sources along the Maine-Quebec border.

[1] Twentieth-century history of the west branch was heavily influenced by the paper mill at Millinocket, Maine.

The Bangor and Aroostook Railroad bridged the west branch near Quakish Lake in 1894; and the Maine legislature chartered the Northern Development Company in 1897 to create and sell hydroelectricity for manufacturing.

A dam was completed at the outlet of Quakish Lake diverting flow through Ferguson Pond and a canal to a paper mill on Millinocket Stream.

The west branch between Quakish Lake and Shad Pond virtually dried up as flow through the canal dropped 114 feet (35 m) through the mill powering eight paper machines producing 240 tons of newsprint per day from groundwood and sulfite pulp.

What was then the largest paper mill in the world began operation in 1900 and within a year had captured twelve percent of the United States newsprint market.

The trail then runs upstream along the river for 3 miles (5 km), until it follows Nesowadnehunk Stream into Baxter Park on the way to its northern terminus on Mount Katahdin.