The claim: This area has seen heavy traffic of foreign military equipment and troops via Illinois Central Railroad, which runs through the area. Suspected location is unknown, but may be close to Vienna and Shawnee correctional centers, located 6 mi. west of Dixon Springs.
What it really is: Completely bogus. Using Google maps I can find nothing that resembles a prison camp inside the national forest that is near the two correctional centers.
As for the claim of foreign military being in the area, none of these claims come from reliable sources, it's just all copy and pasted from other sites without any additional information to back up the claim.