Lake Township is a township that is located in Luzerne County, Pennsylvania, United States. It is part of the Back Mountain, a 118-square mile region in northern Luzerne County. The population was 1,994 at the time of the 2020 census.

The Back Mountain is a region and former census-designated place (CDP) in Luzerne County, Pennsylvania, United States. It is near the cities of Scranton and Wilkes-Barre. The population was 33,551 as of 2016. The region has a total area of 117.59 square miles (304.6 km2). The area was not delineated as a CDP for the 2010 census. The name "Back Mountain" refers to the area's location behind the mountain ridge forming the northwest side of the Wyoming Valley. The area includes the townships of Dallas, Franklin, Jackson, Kingston, Lake, and Lehman. The region also includes the boroughs of Dallas and Harveys Lake. Each township and borough is independently governed.