This walkway joins an original Army zigzag track steeply sloping to Mechanics Bay.

The walkway leads through the tunnel (120 metres) and is lit by natural light.

The lighthouse is visible about the end of the tunnel. Climb back up the hill, past the empty shells of the wartime generator shed, battery plotting room and mini range. Near the site by the picnic area the underground shelters can be identified by the chimney and steel hatches.