KILN is the ICAO code for Wilmington Airpark (IATA ILN), located in Wilmington, OH.
Wilmington Air Park is a public-use airport located two nautical miles (3.7 km) southeast of the central business district of Wilmington, a city in Clinton County, Ohio, United States. While DHL had privately owned the property while operating from the facility, the company agreed to donate the airfield to the Clinton County Port Authority.
Excerpted from Wikipedia, available under the Creative Commons Attribution-ShareAlike License.