Indianapolis Power & Light Company, also known as IPL or IPALCO, is an American utility company providing electric service to the city of Indianapolis. It is a subsidiary and largest utility of AES Corporation, which acquired it in 2000. IPL provides electric service to more than 470,000 customers in a 528-square-mile (1,370 km2) service territory. IPL was formed in October 1926 by the merger of the Indianapolis Light and Heat Company and the Merchant’s Heat and Light Company. Those two companies had started providing electrical service in the 1880s. At the time of the merger, the company had 105,000 customers. In 1937, IPL began a rural electrification program, running power lines to many areas outside Marion County. The company moved into its present-day headquarters building on Monument Circle in downtown Indianapolis in 1935; the building, now known as the Electric Building, had been constructed in 1924 for the Continental Bank. The building was remodeled in 1968 to a design by Lennox, Matthews, Simmons & Ford, with the lighting design by Norman F. Schnitker.