Man-made underground passage in Killalough

Killalough hides a man-made underground passage inside its ringfort, yet no entrance or trench remains visible for modern eyes. Local tradition preserves the tunnel while the earth has swallowed the proof. People may have dug the passage to escape rain, invaders or ordinary boredom, but the soil has erased the exit and changed the function into mystery. What is left is a hole in knowledge rather than a hole in ground, waiting for someone reckless enough to dig or patient enough to listen for water moving through dark stone.