The Kenai Peninsula Borough lies directly south of Anchorage, the State's principal population center. The peninsula extends approximately 150 miles (240 km) southwest from the Chugach Mountains. The peninsula itself encompasses 99 percent of the borough's population and most of the development. The Kenai Mountains run north and south through the peninsula, contrasting to the lowlands lying to their west.
It is separated from the mainland on the west by Cook Inlet and on the east by Prince William Sound. Most of the peninsula is part of the Kenai Peninsula Borough. The peninsula includes several of the most populous towns in southern Alaska, including Seward on the Gulf of Alaska Coast, Soldotna, Kenai, and Cooper Landing along the Cook Inlet, and Homer, along Kachemak Bay, along with numerous smaller villages and settlements.
The peninsula has a coastal climate that is relatively mild, with abundant rainfall. It is one of the few areas in Alaska that allows for agriculture, with a growing season adequate for producing hay and several other crops. The peninsula has one of the state's most diverse economies. Featuring natural gas, petroleum, and coal deposits, as well as abundant commercial and personal-use fisheries.