Staring in to the abyss, these British explorers appear like ants in this giant underground cave.
Venturing deep inside the mammoth Clearwater Cave System under Mount Api on the island of Borneo, the 18-man team of cave explorers and geologists, discovered an extra 20km of cave passages.
Scrambling and climbing through the northern 'Whiterock' section of the Clearwater cave system, the team discovered and named two new dry high level fossil passages 'Borderline' and 'Big Issue'.
They also found an underground river passage and called it 'Whiterock River'.
Spectacular: Geologists survey one of the caverns in the Clearwater Cave System under Mount Api on the island of Borneo
Now measuring 177 km in length, Clearwater is the eighth longest cave system in the world.
Captured by photographer Robbie Shone, these spectacular images document the team's 20-day exploration of the caves.
'Our purpose was to explore the giant caves of Mulu National Park for two months,' said Mr Shone, who is 28 and from Manchester.
'Our team, a joint Anglo-Sawarak caving exploration, mapped, surveyed and photographed as much as we could during the expedition in February and March.'
Mount Api (Gunung Api) is a limestone mountain famous for its striking limestone karst formations, commonly called the pinnacles, however the team focused their exploration in the largely unknown Whiterock section.
With passages measuring up to 15m in diameter, Mr Shone's amazing images show the size and scale of the breathtaking cave system.
British cave explorer Katie Dent stands next to a crystal clear lake in a passage called 1954 in the northern extremities of Whiterock, part of the Clearwater Cave system
'Whiterock is part of the massive Clearwater Cave System and the eighth longest in the world,' he said.
'Exploring the dry and high level passages the team came across two new fossil passages which we named 'Big Issue' and 'Borderline'.
'The most significant discovery had to be the river passage at the very end of the expedition called The Whiterock River.
'Only six days from the end of the two-month expedition, we climbed down a steep ramp with a howling draught blowing up from somewhere - only to find a river passage following a 20m abseil.
'Up until the end of this current expedition Whiterock has also been the high level and northern section to Clearwater, but now that we have found this amazing river passage, I guess that Whiterock is also low level too.'
Led by experienced expedition leader, Tim Allen, the team were joined by Gina Moseley, a PhD student from Bristol University School of Geological Science.
The team could only explore the caves using specialist equipment and spent two months on site
Using specialist equipment, Gina removed samples from the caves and researched them back in the UK to hopefully add more valuable information about their age and how they were formed.
Spending three to four days camping underground the team returned to the surface for one day before repeating the process.
'We would spend no more than four days camping and exploring in the Whiterock part of Clearwater Cave,' Mr Shone said.
'We only stayed in for days right at the very end to push 'The Whiterock River' as hard as we could with our limited time left. I personally wanted as much time to photograph as much as I could.'
Now back in Manchester, Mr Shone will not rule out another trip to the giant caves in 2010.
British cave explorer James Alker looks in amazement at the 'pom pom' like formation that hangs from the roof of a cave
Spectacular underground caverns which are so big British scientists look like ants | Mail Online