GaryChicago International Airport (ICAO: KGYY, FAA LID: GYY) is a joint civilmilitary public airport in Gary, in Lake County, Indiana, United States. It is three miles northwest of the city center of Gary, and 25 miles (40 km) southeast of the Chicago Loop. It is operated by the GaryChicago International Airport Authority, the basis for which was formed by the Chicago Gary Airport Compact