Kate Humble: Into the land unknown – and I can't believe I'm here

Something to Declare

DEEP SOUTH: Evidence of previous encounters awaits 21stcentury visitors to Antarctica (AFP)

We walked down the gangway and on to the Tarmac. I stood nonplussed by the noise of traffic, the sight of buildings, of trees. Two weeks before I had climbed up that same gangway, and on to a ship that would take me across an infamous stretch of water, to somewhere that for centuries was known simply as "terra incognita". I had arrived on the shores of places I had read about, seen photographs of; places synonymous with hardship and extraordinary human valour, with Drake, Cook, Scott and Shackleton. But all those books, the photos, the television documentaries narrated by the mellifluous tones of David Attenborough, none of them prepared me. There is, simply, nowhere on Earth like Antarctica.

We saw our first iceberg on our third day at sea. The much-feared Drake's Passage had proved smooth enough to allow us on deck to enjoy the soaring majesty of the occasional albatross and showy flying skills of the Cape petrels, with their distinctive mottled black and white wings which earn them the Spanish name "pintado".

Our first landfall was on the South Shetland Islands. The fog hung low, veiling the highest peaks in grey, swirling mystery. Chinstrap penguins awaited us on the beach; fearless, curious and as happy to pose for the battery of cameras as any seasoned celebrity.

It may have nothing like the biodiversity of a rainforest, or even an English garden, but the wildlife that inhabits the outer edges of the world's highest, driest continent is plentiful, accessible and largely benign. There are no toothsome hunters like polar bears to worry about, and despite decades of exploitation, which saw the killing of untold thousands of whales, seals and penguins, those same species of animals now give humankind unforgettable close and peaceful encounters that we surely don't deserve.

A female humpback whale and her calf cruised the frigid waters, lazily hoovering up great mouthfuls of shrimp-like krill. I sat with eight other people, in a small inflatable boat, amid towering chunks of floating ice, transfixed. In perfect unison, two smooth, steely grey backs broke the surface of the smooth, steely grey water, their small, blunt dorsal fins carving rippling furrows before vanishing.

"There they are again!" I cried, in a sort of awed stage whisper and for an hour the whales stayed within feet of our boat. The calf raised its strange, knobbly head clear of the water, spy-hopping, and then, perhaps aware that it had a captivated audience, proceeded to roll over, fin slap, lie on its back, wave its tail and occasionally raise its head clear of the water again as if to check we were still watching.

We ran out of superlatives, and sat, smiles stretched across our faces and tears in our eyes. And all around was Antarctica with its harsh, chaotic beauty.

"Is this your seventh continent?" someone asked and dimly I realised it was. But the otherworldliness of it now makes it almost impossible for me to believe I was there. It still remains terra incognita.