Putnam County Airport (GPC), (formerly 4I7), is a public airport 3 miles (4.8 km) southeast of Greencastle, in Putnam County, Indiana, United States.

It is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2017–2021, in which it is categorized as a local general aviation facility.

[2] Putnam County Airport covers an area of 192 acres (78 ha) at an elevation of 842 feet (257 m) above mean sea level.

[3] For the 12-month period ending December 31, 2013, the airport had 7,309 aircraft operations, an average of 20 per day: 99% general aviation and 1% air taxi.

In January 2017, there were 34 aircraft based at this airport: 16 single-engine, 5 multi-engine, 8 helicopter and 5 ultralight.