Long Valley is an approximately 25-mile (40 km) long[1] endorheic basin in the northern portion of Washoe County, Nevada in the northwest corner of Nevada.

It is bordered by the Hays Canyon Range to the west, which gradually transitions into rolling hills north of the valley.

To the east lies a large plateau, which is partially dissected by Massacre Lake Valley; this plateau eventually rises to over 7,000 feet in elevation as it rises toward the Sheldon National Wildlife Refuge.

As part of the events that ultimately led to the creation of the Basin and Range Province, during the late Pliocene and early Pleistocene, basalt was extruded in the Lake Valley region as the surrounding mountains were lifted and the valley floor dropped.

Near Vya, former Nevada State Route 8A intersects with Nevada State Route 34 (now Washoe County CR34), which provides access to Long Valley from Gerlach, Nevada to the south, and Coleman Valley Road, which cuts across Long Valley just north of Vya, veers just east of Calcutta Lake, then heads north toward Adel, Oregon.