‘If you suffer from seasickness, you might want to move away from the front of the ship’ came the ominous call from a crew member as we pulled out of Wellington harbour.

It was soon clear why – and about 40 seconds into my video here explains all.

With some of the roughest seas I’ll probably ever see, the Cook Strait lived up to its reputation as being one of the most notorious stretches of water for mariners in the world.

And being from Grimsby, famous for its fishing and seafaring history, this Mariner was loving every second.

While most of the ship was retching into sick bags, strategically placed around the decks, I was with a few hardier individuals at the front of the ship, watching through windows as we crashed into wave after wave.

Lapping it up like a rollercoaster, we stood and watched as we sailed up the face of huge waves, before rolling down the back and crashing into the next, throwing tonnes of water up and over the ship.

It’s been a late finish and very early start in the past few hours, having been up late seeing out blog duties, before waking up at 4am to watch the England versus France football match in the European Cup. Thanks to the time difference, which means I have to be up at the crack of dawn to watch any of the games, it was the first match I’d seen of the championship.

My hostel, Nomads, had put signs up around the accommodation advertising the match was being shown live in the bar below the rooms, and there was a good 20 or so England fans watching along with me. A good turnout, considering the time, and there was a nod to the few who managed to down a couple of pints before the sun had even thought about rising above the horizon. I stuck to a cup of tea and a bit of toast – after all, what else does an Englishman need when he’s watching his national team?

It’s fair to say it wasn’t the most exciting game of football, but we all agreed we’d accept a 1-1 draw with France before the match. I gathered my bags, had a quick shower and jumped onboard the ferry shuttle bus that was waiting outside the hostel for me.

This is the only part of the journey that I am pretty much on my own for. Touring New Zealand with the Magic Bus makes everything really straightforward when it comes to going from town to town on the islands, but the buses and drivers tend to stay on their designated land masses.

Therefore, I booked myself onto the 8.15am Interislander ferry, one of three huge ships that make the regular three hour, 58 mile crossings from Wellington to Picton, a small town on the tip of the south island.

I noticed that the bow of my ship, Kaitaki, had a more familiar name below it, and one that many will recognise. The paint barely hid the raised ‘Pride of Cherbourg’ that had once been emblazoned on the side – the ferry was one of the main P&O cruise ferries that would cross between Portsmouth and Cherbourg before the route was scrapped a few years ago. At some point, the ferry made the epic sailing from the south coast of England to the deep blue waters of New Zealand, and now makes a couple of sailings a day between both islands in the country. Its still registered to Portsmouth, the city name still painted on everything from the stern to the life belts and lifeboats.

In need of a bit of sleep, I found my way to the reclining chairs, hoping for a good nap before arriving in Picton. The nap never happened. I’d noticed that even while we were at the berth in Wellington, the ship was noticeably pitching even though we were stationary. The waves were already crashing onto the sea defences along the shore, and this was the sheltered harbour area. I had a feeling the crossing might be eventful, confirmed when one of the crew warned us to move away from the front if any of us suffered from motion sickness. I decided to take the chance.

After a bit of fresh air on deck, I watched as Wellington disappeared behind me before the strong wind forced me inside. It was there, looking out of the front windows, that I saw what was ahead. Waves were breaking for as far as the eye could see, and already we were rising and falling on the few that had managed to maintain some height through the harbour wall.

Soon we hit the big ones – smashing down into one huge wave after another. The first time it launched gallons of water over our window, there were gasps and laughter. Hitting the waves at 90 degrees, it was perfect for wave bashing, and there were a fair few of us enjoying the ride.

“The upper and outer decks have been closed for safety reasons,” came one announcement as the swell began to throw all 22,365 tonnes of ship around like a toy in a bathtub.

“Due to the inclement conditions, please only move around the ship if absolutely necessary,” came another.

At one point, every wave we hit was jolting the ship, the bow throwing up a huge white wave and spray every time it smashed into the next wave. People had noticed the spectacle out in the front, and were arriving to take their own photos through the window. Suddenly I had forgotten I was so tired.

After about an hour, we entered the calm serenity of Marlborough Sounds, a beautiful, and thankfully sheltered stretch of water that leads to Picton. Rich in nature and wildlife, we passed the sad sight of conservationists and wildlife experts trying to rescue a whale that had been washed onto the shore. A pod of dolphins effortlessly leaped out of the water alongside the vessel, while beautiful forests, mountains and greenery surrounded the sailing into Picton, a picturesque harbour town.

Most of the passengers had recovered by now, thanks to the calm waters and a lack of wind, and many lined the outer decks to watch as the scenery glides by.

It was still bitingly cold, but enjoyable all the same. Shortly before entering Picton, the ferry is forced to make a sharp s-bend before the town comes into view.

I spent a night at the Sequoia backpackers, being warmed by the cosy log fire and looking forward to some free chocolate pudding, a bit of a perk supplied by the hostel. It would have been lovely had I actually got hold of some – I was eating what has almost now become a nightly bowl of pasta when it was served, but had some put aside for later. Unfortunately, a group of German backpackers decided they wanted seconds and helped themselves to mine. I decided it wasn’t worth the hassle of saying anything, and settled for a couple of biscuits with a cup of tea instead.

After a couple of days of doing my own thing, it was time to rejoin the Magic Bus for my south island adventure. I met Murray, one of the drivers, at the ferry terminal for the short drive to Nelson. One of those also rejoining the bus was Mel, my German friend who travelled with us to Taupo on the north island. After a few days there, she’d made her way south and our paths had crossed again. It was good to see another friendly face, and we laughed about the ferry crossing.

“Oh, mine was lovely, very flat,” she said. Typical!

The road to Nelson took us through the wine-growing region of Marlborough, and we drove past an almost endless line of wineries and vineyards, the browning leaves being the tell-tale sign that harvest season has just been and gone.

Arriving into Nelson late in the afternoon, Murray told us that a great spot to watch the sunset is from the centre of New Zealand, which finds itself on the top of a hill in one of the town’s parks.

“It’ll take you half an hour or two to get there, but it’s a nice walk and the views are worth it,” he said, just before I jumped off his bus.

I quickly learned that night, as I tried to reach the summit of the hill before the sun set behind mountains in the Abel Tasman national park, that if someone tells you a ‘half hour or two’ in New Zealand, it probably means about an hour. And a ‘nice walk’ can mean it’s a mighty steep hill to the top.

Understatements must be a part of school lessons here – and something the captain of the ferry must have mastered for his ‘a few bumps’ assessment.

Murray was spot on about the view though – a panorama overlooking the town, with the flat calm sea bordered by mountains rising up from the national park on the horizon. Behind me, a valley through mountains being framed by a pink and purple sky. A plaque on the ground marks the centre of New Zealand, with a pin-like monument marking the spot.

My photo was taken by a couple who were also admiring the view. I recognised an English accent and asked if they were visiting. It turns out they are a couple of artists, originally from the south coast but who now live in Nelson, and contemplating a move to Byron Bay in Australia. It prompted much chat about how I had been there, our collective thoughts on the place, and discussion about the beauty of New Zealand. I’m pretty sure their names were Andrew and Stephanie, although thanks to yet more problems with my iPhone – its locked itself, complete with all my notes – their names are from memory. I know they said they would check out my site, so if I’m wrong, I apologise!

A name I’ll probably never forget though is that of Soap, our bus driver for the next few days. I’ve deliberately called him our bus driver, because on the first day’s journey with him from Nelson, he made a point of stating he’s a tour guide that happens to drive a bus. He soon changed from tour guide (or bus driver) to that of a good mate – from the moment he welcomed me onboard the Magic Bus, there was a great relationship between him and the dozen or so other people who he was about to tour the south island with.

Soap is someone who loves his job, and showing people from around the world his country. Born in Christchurch but brought up in London, he’s an avid Chelsea fan but supports all things New Zealand, his home. He’s around my age, but done some incredible things with his life, from working in security to driving rushes footage around from the Wolverine movie as it was being filmed. He likes a good laugh too, and as we passed a road sign, explained the story behind an orange teddy bear on his dashboard.

It’s the story of slumps – a cross between a possum and a wombat that only comes out at night, and two Dutch girls he once had on his bus, who he’d nicknamed Tango and Sprite because of their hair colour.

He’d explained to them that the large orange signs you occasionally see by the roadside, with the word ‘SLUMPS’ plastered across them, were a warning to drivers to be on the lookout for the rare animal. The two girls were taken in, and spent the next few days trying to research on the internet about this crazy New Zealand animal called a slump, and wanting to see what they look like.

Of course, they’d fallen for it hook, line and sinker, and Soap ran with it for a couple of days. Slump signs simply warn of dips in the road, but for a while Tango and Sprite believed there was a secret animal few people knew of. When they’d been put out of their misery, they gave Soap a bright orange bear. On his tummy are the words ‘I am a slump’. So now, Soap has his very own slump – and a lot of other momentos and bears – that make the circuits around the south island with him.

We were on our way to Greymouth, and by now we’re really making tracks through the mountains towards the south end of New Zealand. The road winds its way along rivers and through the Lower Buller Gorge, and we’re able to watch from our seats as the beautiful vistas unfold in front of us.

“Hey Peter, you should try to keep track of how many single track bridges there are on the way to Wanaka,” Soap calls to me from the drivers’ seat. I have no idea why he’s just called me Peter, but I let it go. Afterall, he’s got a lot of new people to get to know.

There were a couple of stops along the way, including one where Soap demonstrated how tight some of the roads were by letting us walk ahead and watch as he squeezed his bus along the narrow road at Hawks Crag. Here the road has been chiseled out from solid rock, leaving some overhanging the carriageway.

“If you hear a loud noise, engine breaking, coming from around the corner, its probably a logging truck. Please get out of the way, because they don’t stop,” was his wise advice ringing in our ears as we made our way from the coach to the pickup point on the other side of the pass.

Rocks were the focus of the day, with a later stop at Punakaiki, home of the pancake rocks, an outcrop of stone which has left even geologists baffled as to how they were created. As the name suggests, they look like stacks of pancakes, thin layers of rock laying on top of one another with gaps between.

Its believed the rocks have been formed in this extraordinary way thanks to layers of weaker rock and matter being eroded away by the ocean and battering of waves.

But while the rocks are strange to look at, there is also another aspect of the stop which demonstrated the full power of nature. Within the rocks, there are blowholes and caverns, shapes and crevices formed by the erosive forces of the ocean. And as the huge waves roll in, the sound of them pounding the air from those spaces below the land echoes around the area – a whole range of deep, loud booms that make the ground shudder, such is the force below.

We pulled into Greymouth just before sunset, and Soap called me Peter again. I guess he’ll see my name on the passenger sheet later and correct himself for tomorrow.

In the meantime, after braving the weather as it got colder the further we travelled south, it was time for some new additions to the backpack. We head to the Franz Josef glacier tomorrow, and while I might be able to grin and bear the cold at sea level, it will be a whole new ball game up a mountain on umpteen million tonnes of ice. A trip to local outdoor clothing superstore was in order…

The endless days of hot sun and lazy days by the sea in Thailand seem like another lifetime ago.