Enbridge, Inc. is an energy delivery company based in Calgary, Alberta, Canada. It focuses on the transportation, distribution and generation of energy, primarily in North America. As a transporter of energy, Enbridge operates in Canada and the United States, the longest crude oil and liquid hydrocarbons transportation system in the world. As a distributor of energy, it owns and operates Canadas largest natural gas distribution network, providing distribution services in Ontario, Quebec, New Brunswick and New York State. The company was initially incorporated by Imperial Oil as Interprovincial Pipe Line Ltd. (IPL) on April 30, 1949 shortly after Canadas first major oil discovery at Leduc, Alberta. At the same year the company built its first oil pipeline from Leduc to Regina, Saskatchewan. In 1950, it was expanded through Gretna, Manitoba, to Superior, Wisconsin, in the United States. To operate the United States portion of the pipeline, the Lakehead Pipe Line Company (now: Enbridge Energy Partners) was created. In 1953 the pipeline was expanded to Sarnia, Ontario and in 1956 to Toronto and Buffalo, New York. In 1953, IPL was listed on the Toronto and Montreal exchanges.