The ultimate day for surfers who snowboard?

“It’s going to be big, real big.” My heart skips a beat, but then it’s been highly irregular all morning; I’ve barely slept all night thinking of giant Southern Ocean swells and hungry great white sharks.

Our helicopter’s rotor blades start up as I change from warm clothes into a thick wet suit with rubber booties and a hood; meanwhile more than 50 centimetres of fresh snow that fell overnight coats the earth around me.

“If this isn’t surreal, then nothing is,” Morland says. “In half an hour we’ll be surfing the west coast.” If you thought every possible activity had been thought of here in the adrenalin capital of the ski world, then think again. This ski season you’ll have the option of surfing some of the world’s most remote waves, then skiing the southern hemisphere’s best backcountry mountains – all in one day.

We climb quickly into a perfect blue sky, and head out over the seemingly endless mountains behind Queenstown. We hover in low over the Southern Alps – mountains here jut 3000 metres high, while hidden alpine rivers and massive, mirrored lakes appear far below us on each turn we make.

Fifteen minutes later, white mountains and jagged black-rock escarpments give way to coastal rainforest and billiard-table-green covered mountains just as high as their snowy counterparts; and then, just like that, the great Southern Ocean appears. It looks angry as hell, like a snarling beast, spray rising off swells that originated thousands of kilometres away in the Antarctic. “Anyone else see that?” Morland asks with a slow whistle.

What does he think? Can’t he hear me hyperventilating into the microphone of my headphones?

“It’s big, man, and down there, there’s three or four surfers spread out over 300 kilometres of coastline,” he continues. “There’s no way in except by helicopter, or by trekking for six days or so on the Hollyford Track.” Here lies some of the Antipodes’ most remote coastline – there are no roads here, nor locals (except visiting fishermen), and the closest town’s hundreds of kilometres north at Haast.

Oh, and this is also where big wave- surfing crazies Tom Carroll and Ross Clark-Jones battled some of the biggest waves on the planet in the 3D action movie Storm Surfers.

We bank in low over aptly named Big Bay, and while the size of the waves dries every bit of saliva I have left in my mouth, I can’t help but be transfixed by the beauty of this place. The water’s the perfect turquoise blue tourists travel each year to Queensland’s Whitsunday Islands for, yet there’s no one here at all to see it; seals line the beaches and behind the coast, jagged green peaks stick out of an empty, rugged hinterland. We land on the smoothed-down rocks of the bay, just 20 metres from the ocean. I wax up my board as 2.5-metre-high set waves close out the bay.

It’s not always this big on the west coast; the tour caters for surfers of all abilities and some days here can be gentle and relaxing, it’s just that we’re on the tail end of a gigantic seven-metre swell pattern.

Unfortunately I got to be here for it.

Morland leads me to the rocks he says are safest to jump off. We leap together. The shock of the coldwater forces me to paddle harder, though it’s still not as cold as I expected (currents that come to the area from Australia keep it warmer here than further south and north).

We paddle off diagonally, avoiding the massive waves that swamp the bay. I can’t help but think about what creatures lurk beneath.

“I’ve surfed here for 10 years and I’ve got all my limbs,” Morland says.

“They’re around. Throw out a fishing line and you’ll catch a great white easy, but they’re well fed, so don’t worry.” I make it out the back but I have no intention of catching a wave – they’re the height of two-storey buildings. Looking back at the coastline, past the thrashing shore break to the mountainous hinterland, is enough forme. I paddle back in and change into snowboarding gear on the beach as the pilot starts the chopper to keep the sandflies at bay.

We circle Big Bay, then head back towards Queenstown, passing in low over countless glaciers before stopping for lunch beside Lake Wakatipu in the tiny village of Glenorchy. We stop to pick up a heliski guide at Queenstown Airport then fly up to the empty peaks behind. As we land, swirling powder snow pirouettes in the sky around us. I lie spread-eagled in 50 centimetres of fresh, dry snow as the chopper flies off.

For two hours I ride some of the driest, deepest snow I’ve experienced anywhere in the world. The runs are so long and the snow’s so deep – at times it reaches my waist – that at the bottom my legs burn with cramp. On most runs I’m forced to stop and stretch along the way.