Mystery will forever surround the death of a young NSW man who vanished while caving in remote Tasmanian wilderness more than 50 years ago.
John Patrick Boyle was 26 when he disappeared in October 1969 at Mt Anne in the state's rugged southwest.
Mr Boyle was out with three friends from a caving group when one asked him to retrieve a jumper from a vertical cave entrance.
He seemingly set off in the right direction but was never seen again.
In findings published on Tuesday, coroner Simon Cooper said he was convinced Mr Boyle died on the slopes of the mountain.
"How he died will, I think, remain a mystery," Mr Cooper wrote.
"He may have fallen in a pothole or through horizontal scrub or succumbed to hypothermia. But it is impossible to say."
No one has seen or heard from Mr Boyle since and there was no evidence of him being alive after that day, Mr Cooper wrote.
His friends searched into the night after realising he was missing before air and ground crews, including navy personnel, arrived in the days following.
The coroner made no formal recommendations, noting safety equipment had changed dramatically since then.
"However, the danger posed by the Tasmanian wilderness has not changed," he wrote.
"Those who venture into remote areas ... must be properly equipped and recognise that the responsibility for their safety ultimately rests with them."
Mr Cooper said if Mr Boyle was carrying a whistle the outcome "may have been different".
Mr Boyle, who was born in Mullumbimby in northern NSW, had moved to Tasmania several months before going missing partly to pursue caving.
