Spending the night on the Greenland Ice Sheet, where the sun never sets and the ice never stops moving, is an adventure unlike any other.

My crampons scratched and clawed at the ice as I hauled an equipment-laden sledge up ridge after icy ridge. The whiteness extended far ahead of me to the distant horizon. Panting from exertion, I followed our group to a dip in the ice that offered rare shelter from the wind and unforgiving terrain. Carl, our guide, announced that we'd arrived at our camping spot and we quickly got to work screwing in the ice pegs that would stop our tents blowing away. As I paused to soak in the Arctic landscape of the Greenland Ice Sheet, I knew that this overnight camping trip would be unlike anything I'd ever experienced.

There aren't many places that are still almost unknown, but the Greenland Ice Sheet is one of them. Covering 80% of the world's largest island, it's one of the most extreme environments on Earth. Yet, as Greenland starts to open to tourism, with new flights linking the Danish-administered island to the world, a few adventurous visitors like me are venturing onto the ice.

The easiest access is from Kangerlussuaq, a small town in western Greenland. In 1999, to test their cars in the harshest winter conditions, Volkswagen built a 35km long dirt road leading from the town to the very edge of the ice sheet. Now, however, the ice has retreated so much you need to walk around 1km from the end of the road to get to the sheet. The transition from soft tundra to mud and ice shards and then the ice sheet proper is fast and dramatic.

The scale of the Greenland Ice Sheet – which is the second biggest in the world after Antarctica – is mind boggling. It is up to 3km thick and spans 1.7 million sq km. Its mass, measured in the trillions of tonnes, is so heavy it has pressed much of Greenland's bedrock below sea level. Scientists have dated some basal ice and sediments to more than two million years old – older than our species itself.

Due to the scale of the ice sheet, the ferocity of the climate and the harshness of the terrain, travellers can only visit with a qualified and registered guide. Most trips are day or half-day excursions; just one company, Albatros Arctic Circle offers overnight camping tours. Before heading out, our group of six was briefed and and our gear checked. Nerves gave way to awe as our we stood on the edge, staring into a meltwater river cutting deep........

© BBC