Buttonville Municipal Airport or Toronto/Buttonville Municipal Airport (IATA: YKZ, ICAO: CYKZ) is a medium-sized airport in Buttonville, Ontario, Canada, within Markham, bordering Richmond Hill and 29 km (18 mi) north of downtown Toronto. It is operated by Toronto Airways Limited. Due to its proximity to Toronto's suburbs, there are several strict noise-reduction procedures for aircraft using the airport. There is a weather station located at the airport. The airport is open and staffed 24 hours a day, 365 days a year.