Abby Barrows clips in, about to drop down into Midnight Hole, Tasmania Photo by YD Bar-Ness__1600px

Claire Brett at the National Gallery entrance, Lune River Caves, Tasmania

Claire Brett squeezing into March Fly Pot, Tasmania Photo by YD Bar-Ness

Gavin Brett, down in March Fly Pot, Tasmania Photo by YD Bar-Ness

Goodbye to the sun, entering Midnight Hole, Tasmania Photo by YD Bar-Ness

Ken returns to the sunlight after underground explorations- Photo by YD Bar-Ness

Ken shows off his absolutely brand new shiny trog gear....moments before permanently muddying them. Lune River Caves, Tasmania- Photo by YD Bar-Ness__1600px

Our rescue dummy, and Steve Bunton, Tasmamia Photo by YD Bar-Ness__1600px

Steve Bunton rescues a dummy on an underground rescue practice- Photo by YD Bar-Ness__1600px