Into the blue: Stunning images from within Iceland's tallest volcano

By Jill Reilly
Updated: 12:06 EDT, 23 December 2011

Glistening in the setting afternoon sun of an Icelandic winter, the Crystal Cave of Svmnafellsjvkull (CORR) in Skaftafell national park, highlights nature's beauty.

Created by the awesome forces of the Vatnajvkull ice cap in the south of the volcanic island, the deep blue cave was formed by the glacier meeting the coastline.

The centuries old ice that has come from the slopes of 6,921 feet tall Vrffajvkull, Iceland's tallest active volcano, has compressed all air out of the ice adding to the texture and colour of the cave.

Nature at its best: Created by the awesome forces of the Vatnajvkull ice cap in the south of the volcanic island, the deep blue cave was formed by the glacier meeting the coastline

Changing size: Accessible through a 22-foot entrance on the shoreline, the cave tapers to a tight squeeze at the end no more than four feet high

Accessible through a 22-foot entrance on the shoreline, the cave tapers to a tight squeeze at the end no more than four feet high.

'Blue ice like this deep blue occurs over hundreds of years and begins when simple snow falls onto ice or in this case a glacier,' said 35-year old photographer Orvar Thorgeirsson.

'The snow sticks to the ice and has its air bubbles forced out during the movement of the glacier or transit of the ice.

'Then this snow freezes more to become ice crystals and becomes clearer.

Evolved: The centuries old ice that has come from the slopes of 6,921 feet tall Vrffajvkull, Iceland's tallest active volcano, has compressed all air out of the ice adding to the texture and colour of the cave

Not completely silent: Visitors to the cave can hear cracking sounds as the cave moves along with the glacier

Traveling to the cave from his home in Reykjavmk, Orvar was in awe at the 150-foot long and 16 foot wide natural wonder.

'The ice becomes a blue colour like water is under the ocean,' said Orvar.

'It is about the light being absorbed through the hydrogen in the water and is a beautiful thing.'

The Vatnajvkull glacier on Iceland is the largest one in Europe by volume with an average thickness of 400 m and a maximum of 1,000m.

'Ice caves are in general unstable things and can collapse at any time,' said Orvar.

'They are however much more stable in winter when the cold temperatures harden the ice.

'Even so we could hear constant cracking sounds inside the cave.

'It was not because it was going to collapse but because the cave was moving along with the glacier itself.

'Each time the glacier moved a millimetre loud sounds could be heard.'