The bodies of two men killed in a suspected cliff fall have been discovered at a popular but remote rock-climbing location in the Flinders Ranges.

Key points: A 62-year-old and a 44-year-old died at the remote Moonarie climbing area

A 62-year-old and a 44-year-old died at the remote Moonarie climbing area Police are yet to recover the bodies, with specialised teams to begin the operation this morning

Police are yet to recover the bodies, with specialised teams to begin the operation this morning The rock-climbing spot at the south-eastern end of Wilpena Pound is extremely remote

Emergency crews were called to the Moonarie climbing area in Wilpena Pound at about 1:15pm on Sunday, when the two Adelaide men did not return to their camp.

Police said the men — a 62-year-old from Norwood and a 44-year-old from Fairview Park — were later found dead in the area.

It is believed they fell to their deaths in what police described as "extremely remote" and "inaccessible terrain".

An operation to recover their bodies is expected to begin this morning.

Officers from SA Police Special Tasks and Rescue (STAR) are expected to fly to the area and be assisted by local patrols and State Emergency Service (SES) volunteers.

Police are investigating the men's deaths and will prepare a report for the coroner.

"The two guys involved — just amazing individuals and really unique [and] wonderful characters in the South Australian community as well, and they'll be sorely missed," experienced climber Rob Baker said.

The Climbing Club of South Australia also paid tribute to the victims on social media.

It said it "couldn't be more sad about the situation that has occurred".

"Our thoughts and love for those two climbers," it wrote.

The Moonarie climbing area is at the south-eastern end of Wilpena Pound, about 40 kilometres north-east of Hawker.

A Victorian man fell to his death in the same climbing area in 2014. ( ABC News: Matthew Doran )

On its website, the club describes the spot as the "jewel in South Australia's crown".

"[It] has it all, great climbs, soaring cliffs and that real get away from it all feeling. Moonarie is a remote location with no facilities, not an area for beginners."

In 2014, a Victorian man was killed at Moonarie when he fell 50 metres onto a ledge.

It took more than eight hours for his body to be recovered.

'One of Australia's best climbing areas'

Mr Baker, who co-wrote the book Moonarie: A Rock Climber's Guide, said the circumstances of the accident were still being investigated.

But he said the most likely cause was what was known as an "anchor failure".

"What we ended up with was two climbers roped together on the ground. They were starting around 20 metres above the ground," he said.

"You start from the bottom and as you climb up you're belayed from the bottom … you build an anchor when you get to a rope-length up.

"If you are up on a ledge above the ground, then you generally have an anchor holding you to that ledge, because one of the biggest risks is something we call a 'factor-two' fall where the lead climber falls on to the belayer.

"That's really the most likely cause, especially if two climbers are found roped up together."

Emergency services in the Flinders Ranges near the men's campsite. ( ABC News )

Mr Baker said climbers who tackled Moonarie tended to be "extremely cautious".

"It's one of Australia's best climbing areas, it's a wilderness climbing area. Absolutely majestic," he said.

"People from all over the world visit the place and rave about the quality of climbing."

Mr Baker has spent time climbing in the area over the past 25 years, and said there were about 1,000 different paths ranging "from 10 metres to 120 metres" above the ground.

"It is hard to access. It's about a 40- to 50-minute walk up to the cliff from where you camp at the bottom, so it's a steep uphill," he said.

"When you're climbing … it's soaring cliffs right above the desert. It's just amazing, a really special place."

Local tour operator Paul Keen described the area as "extreme".

"I've seen people hanging off the side and I just have a quick prayer that they climb safely," he said.