Benton County (pop. 175,177) is bordered by the Columbia River on its north, south, and east sides.

It is one of nine Benton counties in the U.S. and one of seven named for Thomas Hart Benton (1782-1858), U.S. senator from Missouri and a strong advocate of the country’s westward expansion.

Benton County is best known for the 586-square-mile Hanford Site, established in 1943 as part of the Manhattan Project to produce plutonium for the first nuclear bombs. The small town of Hanford was abandoned when the Hanford Site was built.

Today, a main focus at the Hanford Site is the environmental cleanup; the site also has an operating nuclear power plant and various centers of scientific research.

The Hanford Reach is a 51-mile, free-flowing area of the Columbia River, much of it adjacent to the Hanford Site.

The county seat of Benton County is the city of Prosser (pop. 5,714), located on the Yakima River in the western part of the county.

Most of the population of Benton County lives in the Tri-Cities area of Richland, Kennewick, and Pasco. along the Columbia River. Richland and Kennewick are in Benton County.

Kennewick (pop. 73,917) is the largest of the Tri-Cities. It is famous for Kennewick Man, a prehistoric man from about 7000 B.C., who was discovered along the Columbia River there in 1996.

The Cable Bridge (1978), connecting Kennewick and Pasco, is one of seven major bridges in the Tri-Cities area.

The 7,700-seat Toyota Center (1988) in Kennewick is the home of the Western Hockey League’s Tri-City Americans and the Indoor Football League’s Tri-Cities Fever.

Richland (pop. 48,058) is the home of Washington State University Tri-Cities, founded in 1989. At Richland High School, the sports teams are known as the Bombers.

Actress Sharon Tate was Miss Richland of 1959. She was one of five people killed by the Manson Family in 1969 in Los Angeles.

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