Dos Rios is an unincorporated community

Unincorporated area

In law, an unincorporated area is a region of land that is not a part of any municipality.To "incorporate" in this context means to form a municipal corporation, a city, town, or village with its own government. An unincorporated community is usually not subject to or taxed by a municipal government...

 in Mendocino County

Mendocino County, California

Mendocino County is a county located on the north coast of the U.S. state of California, north of the greater San Francisco Bay Area and west of the Central Valley. As of the 2010 census, the population was 87,841, up from 86,265 at the 2000 census...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

. It is located 7 miles (11 km) east-southeast of Laytonville

Laytonville, California

Laytonville is a census-designated place in Mendocino County, California, United States. Laytonville, is located north-northwest of Willits, at an elevation of 1670 feet...

, at an elevation of 961 feet (293 m).

The Two Rivers post office opened in 1912 and changed its name to Dos Rios in 1915. The name comes from the place's proximity to the confluence of the Middle Fork of the Eel River

Eel River (California)

The Eel River is a major river system of the northern Pacific coast of the U.S. state of California. Approximately 200 miles long, it drains a rugged area in the California Coast Ranges between the Sacramento Valley and the ocean. For most of its course, the river flows northwest, parallel to the...

with the Eel River proper.