There is little routine data on vaccination coverage among adolescents in France at the subnational level. However, it is important for regional health agencies to have accurate indicators at the health region level in order to implement vaccination promotion policies and targeted catch-up campaigns. The objectives of this study were to document vaccination coverage among adolescents in Calvados, as well as their knowledge and perceptions regarding vaccination and vaccine-preventable diseases. A descriptive cross-sectional study measuring vaccination coverage (all valences combined) among adolescents summoned to six randomly selected Defense and Citizenship Days, who were asked to bring their health records. Data on knowledge, attitudes, and perceptions were collected via a self-administered questionnaire. Vaccination coverage for the second pertussis booster was 59.6%, two doses of MMR at 92.1%, meningococcal C at 22.2%, three doses of hepatitis B at 37.5%, and two doses of HPV at 25.3%. A majority (81.2%) of adolescents believed they were up to date on their vaccinations; 88.7% considered vaccination useful/very useful; 61% feared its side effects; and only 22.5% were aware of a vaccine against meningococcal C. Vaccination coverage rates among adolescents in Calvados are insufficient and require the implementation of targeted catch-up campaigns. Adolescents view vaccination fairly positively but lack knowledge about the diseases against which they are or could be vaccinated.