State Route 140 (SR 140) is a two-lane state highway in Humboldt County, Nevada. It serves a sparsely populated section of the state, connecting northwestern Nevada to southern Oregon. Most of the highway was originally part of State Route 8A, and was later improved through an effort to provide an all-weather highway linking northern Nevada to the Pacific Northwest. Route description State Route 140 begins at a junction with U.S. Route 95 about north of Winnemucca in the Quinn River Valley. From this point, the highway heads west towards the sparsely populated regions of northwestern Nevada. SR 140 crosses into the Desert Valley before entering a branch of the Fort McDermitt Indian Reservation. Inside the reservation, the route crosses the Quinn River. Upon exiting the Indian territory, SR 140 curves northwest to parallel the Quinn River for about as it rounds the northern edge of the Jackson Mountains. As the river turns southeast towards the Black Rock Desert, the highway continues its northwest trajectory through the valley between the Bilk Creek Mountains on the east and the Pine Forest Range to the west. The route crosses over the Denio Summit before reaching Denio Junction. State Route 292 intersects the highway here, providing access to Denio, the only town in this region of Nevada. At Denio Junction, State Route 140 turns westward past the south end of the Pueblo Mountains. About from the junction, the highway enters Virgin Creek Valley. The valley has been known for its black fire-opals, and some mining operations in the area will allow civilians to hunt for the precious stones for a fee. Near this valley, SR 140 enters the Sheldon National Wildlife Refuge, an area designed to provide habitat for pronghorn and conserve native fish, bird and plant species. The highway travels about through the wildlife range towards the Oregon state line. SR 140 ends at the border in the northwest corner of Humboldt County, with Oregon Route 140 continuing northwest towards Adel and Lakeview. History Much of the State Route 140 alignment can be traced to the early years of Nevada's state highway system. A road roughly following about of the southern end of the current alignment was in place by 1919. However, instead of entering Oregon en route to Adel, the road veered westward through Washoe County towards Vya and Cedarville, California. By 1929, this alignment had been established as State Route 8A.