Google will soon expand its fiber-optic high-speed Internet service in San Francisco. Alphabet said Wednesday that it would add its one-gigabit-a-second Internet service to apartments, condos and public housing in parts of San Francisco, making it the 11th U.S. city with existing or planned Fiber service.

Alphabet built its own fiber-optic network in Kansas City; Provo, Utah; and Austin, Texas.

Alphabet said Fiber in San Francisco will be limited to places that touch the fiber-optic cables it plans to use. The company said it is not considering single-family homes in San Francisco for Fiber, at least to start, because it wants to serve denser communities first and because many single-family residences aren’t close to the existing cables.

Google's parent company has also named another 11 cities for potential expansion, including Chicago and Los Angeles.

Alphabet typically charges $70 a month for the fastest version of Fiber. The company also offers an effectively free basic Internet connection at five megabits a second.