The tunnels extend the growing season for high value crops.
The tunnels can extend deep into the ground, at least 30 feet, and there usually is more than one main entrance.
The tunnel extends from the Sun in the direction of 10 o'clock.
To that point men had worked in tunnels extending 840 metres (2,800 feet) below the ground.
If the tunnel had ever extended beyond this point, it had collapsed in on itself.
The tunnels also extend beyond the platforms into the "Overrun".
The tunnel extended for more than a kilometer, and its lower sections were knee- deep in water.
Anyway, the tunnel does extend downward from the city.
Locals say the man-made tunnels in the cliffs extend for about four miles.
The abandoned tunnels extend some distance in either direction from St James.