Janesville (also, Gas Point and Lassen) is an unincorporated community in Lassen County, California. It is located 11 miles (18 km) southeast of Susanville, at an elevation of 4239 feet (1292 m). Janesville is located on the eastern slopes of the Sierra Nevada Mountain range. As of the 2000 census. it had a population of 3,089.
The community consists of an elementary school, a park, three churches, two gas stations, a pizza parlor, a coffee shop, a veterinary hospital, a recently closed feed store, a hardware store, a post office, and a few other businesses.
Janesville stretches over a distance of 8 miles (13 km). Its ZIP Code is 96114. The community is inside area code 530.
Janesville is also home to Mankins Ranch, also known as the Janesville Bear Dance site, located southeast of Highway 395.
In 1860, after the Battle of Pyramid Lake (also known as the "The Ormsby Massacre"), settlers built a loopholed stockade for protection from an Indian attack that never materialized. The fort, which had a bastion, or block house, in its southwest angle, was less than a mile from the town of Janesville. The site of the fort is now a California Historic Landmark.
In 1864, Janesville lost to Susanville by one vote from becoming the county seat.
In the state legislature Janesville is in the 1st Senate District, represented by Republican Dave Cox, and in the 3rd Assembly District, represented by Republican Rick Keene. Federally, Janesville is located in California's 4th congressional district, which has a Cook PVI of R +11 and is represented by Republican John Doolittle.