New Zealand's most prestigious photography prize, New Zealand Geographic Photographer of the Year, has gone to intrepid adventure photographer Neil Silverwood.
He is a specialist caving photographer, spending weeks at a time underground, and his winning portfolio for the Nikon Photographer of the Year Award takes viewers on a journey into one of New Zealand's deepest, darkest and most dangerous underground environments: the Ironstone cave system.
Justin Gregory speaks to him in Nelson, just before he sets off on another adventure into the Kahurangi National Park.
You can see all of the finalist entries in a free exhibition at Auckland Museum until 25 February 2018.