While most climbers like to scale the outside of a mountain, one daring photographer ventured into the depth of the Canadian Rockies to unveil its frozen secret.
Canadian photographer Paul Zizka climbed into the heart of the Booming Ice Chasm, a 459 feet deep fissure inside Sentry Mountain, to capture a world that will never melt.
Inside, crystal clear blue sheets of ice slides line the chasm. Because of the ice's solidity, some explorers have described moving along its surface as a feeling like flying.
He said: 'Places like the chasm are one-of-a-kind and are to be treasured.
'Being able to document such a surreal place was certainly a highlight of my career as a photographer.
'And it was also probably one of the most technically challenging photo opportunities I have ever had as well.'
Communication inside the chasm can be extremely difficult due to a never-ending echo.
Zizka explained: 'Besides the darkness and the technical terrain, the acoustics make it quite hard to communicate with the rest of the team.
This means when speaking to each other, the explorers had to wait seconds after each syllable.
However, the chasm has proven to be one of the best places that the photographer has visited.
Zizka, who specialises in mountain landscape and adventure photography said: 'I think I have seen my share of cool places, but words escaped me as I saw the tongue of blue ice vanish into the depths of Sentry Mountain.'