Thetford of Reef Cathedrals is located to the east of Cairns. Almost 2km long reef with scattered coral heads Take a long safety sausage as its easy to become disorientated Between the bommies sandy floors are covered with smaller coral patches and numerous blue staghorn thickets. In the smaller coral patches look for giant clams, butterflyfish, rabbitfish, damsels, angelfish and pipefish. On the bommies you'll be confronted with many swim-throughs The swim-throughs are partially closed on top, sending magical shafts of light down the mysterious passageways Take special care in the passageways while passing the large gorgonian fans and soft coral. Anemones host several species of commensal fish and transparent shrimps Boulder coral heads have dozens of multi-coloured Christmas worms