Historical Timeline

1848 Washington Gas Light Company received charter from Congress
1917 Washington Gas purchased Rosslyn Gas Company in Virginia and added it to
controlling interest already held in Georgetown Gaslight Company
1939 Alexandria Gas Company, founded in 1851, acquired by Washington Gas
1959 Washington Gas acquired Shenandoah Gas Company
1963 WGL announced that a new subsidiary, Hampshire Gas Company, planned to
acquire and operate a natural gas field in West Virginia
1964 Stock of Frederick Gas Company (MD) acquired by Washington Gas
1996 Frederick Gas Company merged into parent Washington Gas
1998 Washington Gas sold West Virginia distribution assets to Mountaineer Gas
2000 Shenandoah Gas Company merged into parent Washington Gas
2000 WGL Holdings, Inc. established and became the parent holding company for
Washington Gas Light Company and each of its subsidiaries
2018 WGL Holdings, Inc. and AltaGas Ltd. successfully complete merger, with WGL Holdings and all of its subsidiaries, including Washington Gas Light Company becoming wholly owned subsidiaries of AltaGas.