The Fremont National Forest is the eastern portion of the Fremont-Winema National Forest, which combined comprises a significant portion of south-central Oregon. Yamsay Mountain is located in the extreme north-northwest of the forest region.
The Fremont National Forest is located in the eastern part of the Fremont-Winema National Forest, which spans a significant area of south-central Oregon.  Yamsay Mountain is found at the very northern edge of the Fremont National Forest.