The Humboldt River is an extensive river drainage system located in north-central Nevada. It extends in a general east-to-west direction from its headwaters in the Jarbidge, Independence, and Ruby Mountains in Elko County, to its terminus in the Humboldt Sink, approximately 225 direct miles away in northwest Churchill County. Most estimates put the Humboldt River at 300 to 330 miles long however, due to the extensive meandering nature of the river, its length may be more closely estimated at 380 miles (610 km). It is located within the Great Basin Watershed and is the third longest river in the watershed behind the Bear River at 355 miles (571 km) and the Sevier River at 325 miles (523 km). The Humboldt River Basin is the largest sub-basin of the Great Basin encompassing an area of 16,840 square miles (43,600 km2). It is the only major river system wholly contained within the state of Nevada.

Nevada is a landlocked state in the Western region of the United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, the 32nd-most populous, and the 9th-least densely populated of the U.S. states. Nearly three-quarters of Nevada's people live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City. Las Vegas is the largest city in the state.