San Bernardino County: in California is the largest county in the United States by area with a total surface area of 20,105 square miles! It is also the largest county in California .
Apache County: is located in the northeast corner of Arizona. Apache County has a total land and water surface area of 11,218 square miles.
Coconino County: in Arizona has a total area of 18,661 square miles of which 18,619 square miles are land and 43 square miles (0.2%) are covered by water.
Inyo County:With a total land and water surface area of 10,192 square miles, Inyo County is the ninth-largest county by area in the U.S and the second-largest in California.
Sweetwater County:has a total land and water surface area of 10,491 square miles –larger than six individual states put together! As of the 2020 United States Census, the population was 42,272.
Nye County:At 18,159 square miles of land and water area, Nye County is Nevada’s largest county by area and the third-largest county in the United States.
Harney County:is the tenth largest county in the United States and the largest in Oregon. It is, in fact, larger in area than six U.S. States combined! Harney County was named in honor of William S.
Elko County:Established from Lander County in 1869, Elko County was named after the county seat of Elko. With a total land and water surface area of 17,203 square miles.
Mohave County:This is the fifth-largest county in the United States, with a total land and water surface area of 13,461 square miles. Located in the northwestern part of Arizona.
Lincoln County:While only the third-largest county by area, it is the seventh-largest county by area in the United States, with total land and water surface area of 10,637 square miles.