St. Catharines/Niagara District Airport (IATA: YCM, ICAO: CYSN) is a regional airport located in Niagara-on-the-Lake, Ontario, Canada. It is classified as an airport of entry by NAV CANADA and is staffed by the Canada Border Services Agency on a call out basis from the Queenston-Lewiston Bridge. CBSA officers at this airport currently can handle general aviation aircraft only, with no more than 15 passengers.