World Facts

Largest Counties In The US By Area

Ranked by total (land and water) surface area, all of these are found in the Western US. They are all also larger than many of the world's countries!

The United States Census Bureau published a list on the largest counties in the United States in 2010. The list is for the largest counties when including both land and water surface counts as part of the size thereof. The largest counties are all found situated in the western United States. Despite the definition, no counties with significant water surface proportions are not included in the list. The state of Alaska is exempted, as there are no counties in that state, but instead census areas and boroughs. Some counties listed do not have significant water surface at all, but are included due to the massive land surface areas that they span. When considering that all of the counties listed herein have total surface areas in excess of 10,000 square miles, consider that Rhode Island, Delaware, Connecticut, New Jersey, New Hampshire, and Vermont. The largest county herein, San Bernardino, is larger than 9 US states, and is close to the same size as the nation of Croatia.

10. Harney, Oregon (10,226 square miles)

Harney County in Oregon is the tenth largest county in the United States. The county was named after a military officer in 1889. Its total land and water area is 10,226 square miles. Its population, as of 2014 estimates, is about 7,126, of which is dominated in number by Whites, followed by Native Americans, Hispanics, Asian Americans, African Americans, and Pacific Islanders. It also has a small Spanish Basque population living therein. There are a few registered National Historic Sites in the county. Points of interests there include two national forests and a wildlife refuge. Steens Mountain, a wilderness area, is another interesting place in the county.

9. Inyo, California (10,227 square miles)

Inyo County in California is the ninth largest county in the United States. It has a total land and water area of 10,227 square miles. The county was named after an American Indian tribal Shoshone chief. Independence is its county seat. Its 2010 population of 18,546 had a White majority, followed by Hispanics, Native Americans, Asian Americans, African Americans, and Pacific Islanders. There are 17 registered National Historic Places in Inyo County. Two of the key points of interest in Inyo County are Mushroom rock, a rock formation created by erosion, and the Five Bridges Impact Area, a meadow that has been dewatered.

8. Sweetwater, Wyoming (10,491 square miles)

Sweetwater County, Wyoming is the eighth largest county in the United States. Its total land and water surface area amounts to 10,491 square miles, which is larger when compared to three individual states in their entirety. It took its name from the Sweetwater River. The county had, as of 2010, a total population of 43,806 with Whites predominating, followed by Latinos, Native Americans, African Americans, Asian Americans, and Pacific Islanders. Points of interests there are the three ghost towns of Bryan, Table Rock, and Winton. There are 34 registered National Historic Sites in the county of Sweetwater.

7. Lincoln, Nevada (10,637 square miles)

Lincoln County in Nevada has the seventh largest total land and water area in the United States, covering 10,637 square miles. It is named after President Lincoln. Its population as of the 2010 census was only about 5,345, of which 91.50% were white, 5.31% of Hispanic origin, 2.69% from other races, 1.78% African American, 1.75% Native American, 0.34% Asian, and 0.02% by those of Pacific Islander origins. The county seat is Pioche Template. The famous, or infamous, Area 51 is found in the county. There are three registered historic places and 16 wilderness areas in this vast county alone.

6. Apache, Arizona (11,218 square miles)

Apache County in Arizona is the sixth largest county in the United States. The county has a total land and water surface area of 11,218 square miles. The county seat is St. Johns, and it has a population of 71,218. Of these, Native Americans are the predominate majority, followed by Whites, Latinos, African Americans, Asian Americans, and Pacific Islanders. Points of interest in Apache County are Petrified Forest National Park, the Hubbell Trading Post National Historic Site, the Canyon de Chelly National Monument, and Apache-Sitgreaves National Forest. Religious affiliations here are most Roman Catholic, followed by The Church of Jesus Christ of Latter-Day Saints.

5. Mohave, Arizona (13,470 square miles)

Mohave County in Arizona is the fifth largest county in the United States. Its total land and water area is about 13,470 square miles, and its county seat is Kingman City. The county has a population of 203,361, and this is composed of White, Latino, Native American, and Asian Americans alike. Points of interest are Lake Mead, the Parashant National Monument, and portions of the Grand Canyon National Monument. Indian reservations in the county belong to the Hualapai, Kaibab, and Fort Mojave nations. The wildlife refuges in the county include the Havasu National Wildlife Refuge, Kaibab National Forest, the Pipe Spring National Monument, and the Bill Williams River National Wildlife Refuge.

4. Elko, Nevada (17,203 square miles)

Elko County in Nevada is the fourth largest county in the United States. It has a total land and water surface area of 17,203 square miles. Named after the county seat of Elko, its population of 52,766 people are predominately either European Americans, Hispanics and Latinos, or Native Americans, alone or in combination. Other ethnicities living there include Asian Americans, African Americans, and Pacific Islanders. Points of interest in Elko are the Humboldt-Toiyabe National Forest and Ruby Lake National Wildlife Refuge. Most of the county observes Pacific Standard Time, while Mountain Time is observed by some communities in the county, such as Jarbidge, Mountain City, Jackpot, and Owyhee. This is due to economic reasons connected with the state of Idaho, which is itself on Mountain Time.

3. Nye, Nevada (18,159 square miles)

Nye County in Nevada has about 18,159 square miles of land and water area, making it the third largest county in the United States, and the largest in Nevada. The county was named after James Nye, a former Nevada Governor and Senator. It has a population of 43,946 people. Its environmental programs have succeeded in declaring four areas in the county as being designated animal refuges. Much of its early economy depended on gold mines, and today points of interest for tourists there are the Nevada Test Site, the Ash Meadows National Wildlife Refuge, the White River Valley, the Great Basin Sky Islands, and the Grand Canyon.

2. Coconino, Arizona (18,661 square miles)

Coconino County in Arizona is the second largest county in the United States, with 18,661 square miles of total surface area. Coconino's name comes from Cohonino, another name for the Havasupai Indians living in the Grand Canyon National Park, itself constituting part of the county. The population of about 134,421 people is composed of mostly native Americans from the Navajo, Havasupai, Hualapai, Hopi, and other American Indian nations there. The white population in Coconino is smaller compared to the native American population, and there are five designated American Indian Land Reservations in the county.

1. San Bernadino, California (20,105 square miles)

San Bernardino County in California is the largest county in the United States, at 20,105 square miles including both land and water surface area. San Bernardino is also the fifth largest county in terms of population, with 2,035,210 people as of the 2010 census. Located in the lower area of California, the county is part of the Inland Empire region. San Bernardino and the surrounding mountains took their names from the first church in the area. Most of its population lives in the San Bernardino Valley and the Riverside area. The Victor Valley and its surrounding communities also serve as major residential communities. Besides these, there are large areas of wilderness and protected areas in the county, many of which are often threatened by wildfires and droughts.

Largest Counties In The US By Area

RankCountyStateTotal Area (miĀ²)
1San Bernardino CountyCalifornia20,105.32
2Coconino CountyArizona18,661.21
3Nye CountyNevada18,158.73
4Elko CountyNevada17,202.94
5Mohave CountyArizona13,469.71
6Apache CountyArizona11,218.42
7Lincoln CountyNevada10,636.77
8Sweetwater CountyWyoming10,491.17
9Inyo CountyCalifornia10,226.98
10Harney CountyOregon10,226.49
11Navajo CountyArizona9,959.49
12Malheur CountyOregon9,929.99
13Humboldt CountyNevada9,657.87
14Fremont CountyWyoming9,265.80
15Maricopa CountyArizona9,224.27
16Pima CountyArizona9,188.83
17White Pine CountyNevada8,896.60
18Idaho CountyIdaho8,502.48
19Lake CountyOregon8,358.47
20Kern CountyCalifornia8,161.42
21Yavapai CountyArizona8,127.78
22Clark CountyNevada8,090.66
23Carbon CountyWyoming7,964.03
24San Juan CountyUtah7,933.09
25Owyhee CountyIdaho7,696.71
26Riverside CountyCalifornia7,303.13
27Tooele CountyUtah7,287.12
28Park CountyWyoming6,968.51
29Catron CountyNew Mexico6,929.03
30St. Louis CountyMinnesota6,859.91

More in World Facts