Edison International, through its subsidiaries, engages in the generation and distribution of electric power. The company supplies and delivers through its electrical infrastructure to an approximately 50,000 square-mile area of southern California. It serves residential, commercial, industrial, public authorities, agricultural, and other sectors. The company's distribution network consists of approximately 13,000 circuit-miles of lines ranging from 55 kV to 500 kV and approximately 80 transmission substations; and approximately 38,000 circuit-miles of overhead lines, approximately 32,000 circuit-miles of underground lines, and approximately 730 distribution substations. Edison International was founded in 1886 and is based in Rosemead, California.