We were about halfway up our small climb when a loud crack pierced the air. It was followed by a low rumble from below. Spinning around, I quickly scanned the horizon but my sudden movement saw me slide down the hill a couple of metres, stopping just short of a resting crab-eater seal. Gumboots are not known for their wonderful grip and penguin poo makes for a very slippery surface.
We had panoramic views of the massive glaciers surrounding us from this hillside vantage point. The setting seemed to be just waiting - almost demanding - for something dramatic to happen. As if on cue, a towering block of ice, the size of a small building, carved off the side of an almighty glacier and started a slow slide into the freezing waters below.
We were lucky to witness this sobering demonstration, even if we were in Antarctica, the home of glacial activity. Most carving occurs inside the glacier, so whilst always audibly impressive, it's not always visible.
Antarctica is a land of "-ests": the highest (50 per cent of land here is at least 200m above sea level), driest, coldest, windiest continent on Earth. It also contains two-thirds of all Earth's fresh water. And it is, I now know, the most spectacular place on Earth.
World Expeditions' adventure to Antarctica starts in the small town of Ushuaia, near the southern-most point of Argentina. From there it is a one-and-a-half day boat trip aboard the ice-strengthened ship Plancius, which holds some 114 passengers in surprising comfort, across the Drake Passage to the Antarctic Peninsula.