2017 Map of Arrowrock Reservoir NE

About this map

The northern reaches of the Arrowrock Reservoir dominate the southern boundary of this Boise River drainage, where the water meets the mouth of Cottonwood Cr at the border of Boise Co and Elmore Co. This 2017 survey reveals the high-altitude topography of the Boise National Forest, punctuated by peaks such as Thorn Creek Butte and Bald Mtn. The landscape is defined by a dense network of watercourses, including the Middle Fork Thorn Cr and Easter Cr, which carve through numerous named gulches. Local transit is largely dictated by the terrain, with routes like the Atlanta Road following the reservoir's edge and forest roads such as Going Down Thorn and State Spur providing access to the interior timberlands and mountain ridges.