Nice sunny day out at captain cooks monument. After a failed search for monument mine walked round to find this one, only visable by the fence around we found the metel doors covering the stairs. Further searching down the hill and we found the entrance. After a 5 min crouched walk through the entrance with a pipe running down the middle we where faced with a small cavern with the ladders coming down to it. After going round it looks like it was back filled and possible to get further round unsure tho and wasnt going to squeeze through today.