There are 26 anti-aircraft guns in Far Cry 6. The guns are located in different parts of the map. If you don't destroy them, you won't be able to fly in the given area. When you get close to an anti-aircraft gun, you will be shot down immediately. On this page of our guide, you will find the locations of all the anti-aircraft guns in the Isla Del Leon region.
Location: Northern part of Isla Del Leon island. The only way to get there is by the air. It's a good idea to jump with a parachute, land in enemy territory, and destroy the gun.