[5] Sams River originates on the north slopes of Finley Peak in Olympic National Park.

For several miles the national park and forest boundary runs along the crest of Sams Ridge.

At the western end of the ridge, where the Olympic Mountains open up into broader valleys, the boundary follows Sams River.

The boundary turns south near the mouth of Sams River, leaving the final half mile or so within the national park.

The Queets Ranger Station is located about a mile downstream from Sams River.