[3] The borough seat is Soldotna,[4] the largest city is Kenai, and the most populated community is the census-designated place of Kalifornsky.
The borough includes most of the Kenai Peninsula and a large area of the mainland of Alaska on the opposite side of Cook Inlet.
There is a borough-wide government based in Soldotna, consisting of a strong mayor and an assembly of representatives from all areas of the borough.
They collect sales and property taxes and provide services such as road maintenance, waste collection facilities, emergency services and major funding for public schools, along with mitigation of damage from spruce bark beetles that infested the borough in the late 1990s and early 2000s.
Kenai Peninsula is one of the most Republican boroughs in the state, having last backed a Democrat for president in 1968.