The Florissant Valley Branch opened in 1965, about a year after the Florissant Public Library ceded to the County Library District. The building has been renovated since then, including a 12,000 square foot expansion completed in 1996. The branch is the largest in North County, and features an auditorium, two meeting rooms, and a computer lab which offers free classes. The Florissant Valley Branch is the site of Teen Alley, a dedicated space with its own collection and computers, specifically built to attract area teens. The branch is located within Bangert Park, right next to the swimming pool and in the heart of Florissant.