It's Sunday, September 16th, 2018, in the Arabica Massif, a mountain range in Russian-occupied Georgia.

These towering limestone formations are blanketed in lush woodland. Their snow-tipped peaks loom over the serene waters of the Black Sea,

which fans out into the distance.

But Arabeka's greatest natural feature is below the surface.

Veriovkina.

Officially the deepest cave in the world. From its opening in the mountains, Varyovkina drops straight down,

startling 2.2 kilometers, or more than 7,200 feet. It's a vast vertical chasm right through the heart of

the mountain range. Deep down is a kingdom of slender passageways, echoy caverns, and immense

starkness.

And it's in this world that 38-year-old British photographer Robbie Shone has spent the past two weeks.

He's here documenting the work of a Russian caving team.

He's captured images of the stunning green pools of water at the bottom,

the jutting rock formations, the glistening limestone walls.

He's even visited Veriofkinner's terminal sump, the deepest point in the deepest cave.

Right now though, on Sunday morning, Robbie's tucking into his breakfast.

He and the Russian cavers are huddled under a blue tarpaulin, chowing down in the light of their head torches.

Over the past week, Robbie's grown used to Variofkiners Camp 3, located on a horizontal plateau, 1,900 meters below the surface.

By caving standards, it's pretty luxurious, with a high ceiling,

and soft brown sand blanketing the ground.

The cavers have made themselves at home here, hanging their kit up to dry on washing

lines strung over their heads. Robby's photographic equipment, cameras, lights,

tripods and more is spread out all around the cave. The atmosphere is laid back, relaxed,

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