On day two, the feet do the usual second-day thing - fall to bits - and a man with the strategic skills of Field Marshal Rommel tries to sabotage Te Araroa.

Motupia Island

Ninety Mile Beach extends so far and is so much the same that any object that sticks out of that dust and water strip is visible for miles. An object as unfascinating as a plastic crate possesses nonetheless, for the long hours it takes to reach and identify it, cryptic power. Beyond Te Paki, on the high tide line, stands a 'T'. It appears huge, and its alphabetic form suggests a kind of magnificence, then it reveals itself, in the brief minutes as you actually draw level, as an upended wooden cable drum, hung with small mussels.

Motupia had lain in front of me ever since leaving Scotts Point, but without mystery. An island is just an island, though I wondered why this one, with its distinctive bird-skull shape and socket, had never found itself into any of the coffee table books. Motupia was still a distance off when I saw two vehicles with a string of trailers stop facing the island.

They were not the first vehicles I'd seen on the beach. The tourist buses, almost corny in their bright livery and script - Cape Runner, Sand Safari - use Ninety Mile Beach as a highway and had already splashed up Te Paki Stream when I was pumping water. But these ones - still spindly in the distance - were the first I'd seen stopped.

An hour passed and I was close enough to see the seaweed that lay in a dark roll buffeted by an incoming tide. A Maori gang was working like the clappers. One trailer was half in the tide, and three men with long-handled spatulas were throwing pink seaweed into the trailer with a speed that suggested a race against time. Another couple were working to a long trailer attached to a beaten-up yellow Toyota at the water's edge, and a third man stood on the trailer, swiftly distributing the load with a rake. A Pajero roared up the beach with two empty trailers in tow, slid to a halt, and an older man jumped out. I headed for him, and he saw me coming, but moved away from me, calling instructions to the water gang. The guy leveling the weed in the long trailer finished his task, and jumped down. I grabbed him. I had a map ready and knew no-one could refuse a tramper guidance.

"Hi man. Can you give me an idea which of these streams is running?"

He was young, Maori, with long blonded hair, tats, an earring. He looked harassed.

"This one." He pointed to Pukekura Stream just 10 kilometres up the line, and I marked it in pencil. His eyes kept flicking away like he shouldn't be standing around talking. "The others - maybe not, but you can always follow them in and get water in the forest."

"Great. " I gestured at his load. Seaweed eh?"

"Yeah," And he was gone. I walked on a kilometre, then headed up to dry sand, cooked up a packet soup and watched them. The pace of work didn't slacken. The two 4WDs belted up the beach with full trailers and returned with the empties 15 minutes later, kicking up spray, and the process continued until the dark roll of seaweed that had come in with the tide was gone. The beach was deserted again. Then a Landrover came down, pouring a greasy black exhaust, towing a double trailer and with some rake-like mechanism on the front to allow a one-man seaweed lifting operation. The Landy zeroed onto the patch that the Maori gang had worked. It stopped - you could just about see it sniffing the air. It turned round and went back up the beach. You could just about smell the disappointment. I waved, but no answering signal came back. The Ninety Mile Beachers took their seaweed gathering more seriously than anyone I'd ever seen before.

I was getting sharp tendon pain from my boots. On the second day in, I'd hoped to reach the Bluff, the only headland on Ninety Mile Beach, about a third of the way down. But I was far short of it, and hobbling. I changed to sandals and the tendon pain disappeared, but it took only a few more kilometres before the sandals had blistered every rub point. I treated the blisters with Second Skin, strapped the feet with Sleek, put on a pair of Thorlo socks to further distance sore flesh from the unforgiving sandal edges and kept walking. I was okay, but I already knew I wouldn't get to the Bluff that day.

"Want a ride?"

The ute had come out of the south in the late afternoon, and stopped alongside.

"You're going the wrong way."

"I dropped a board off the trailer - I'm just going to find it, then I'll be going back to the Bluff - hop in."

"I can't. I'm doing the beach on foot. I'm doing the length of the North Island on foot. No rides."

"What - for charity?"

"No - just walking. But you can tell me something. Your trailer. You gather seaweed right?"

"I don't do the seaweed. I'm a fisheries officer. Right, so you're coming or not? I've got to find that board and beat the tide back to the Bluff."

"Why?" I said, "do they gather seaweed?"

"It's not the seaweed," he said, "It's the mussels." Then he was gone.

I walked on up to Pukekura Stream and waited. I didn't want to know about the seaweed any more, I wanted to know about the mussels. And I was sick of walking. I watched the birds. When you're trudging into the featureless distance of the Ninety Mile, it's the dark surge marks of the tide, reaching in places right across the white sand, that are the fata morgana of the beach. They look like the stream that's marked on your map and you want fervently for them to be the stream that's marked on your map, but they never are.

The real fresh-water streams are always heralded by birds. A covey of small black-headed terns and two big Caspian Terns had ushered me into Te Paki. At Pukekura it was black-backed gulls, two pied stilts, shy birds with a cry as thin and red as their legs, and three black oyster catchers, busy with their stick-like orange beaks blind-tapping their way around the shallows.

Twenty minutes later the ute re-emerged from the afternoon haze, and I flagged it down.

"Okay," beamed the driver. "So sling that pack in the back - you want a ride."

"No, I want to know about the beach. I want to know what I'm walking through. I want the stories."

"You want someone who knows the beach? Warren Brown's your man. He's up at the bluff right now, fishing. He's Ngati Kuri. He was born in Te Hapua, went to school here, lives here, he knows about this place like no-one else. Hop in, I'll take you up."

On his particular patch of desert, this guy had the strategic skills of a Field Marshal Rommel.

"Look - " I introduced myself and said - "What's your name?"

"West Hill."

"West - I'd love to come up to the Bluff and talk to Warren Brown, but I can't. I've got to walk the beach."

"Your feet have to touch the sand the whole way right?"

"You've got it."

"Okay - sit on the trailer, hang your feet out the back and make sure they're scraping the beach all the way to the Bluff."

The tide was surging in, and it left little time to talk. But I wanted at least to know about the mussels.

"Mussel spat," said Hill. "It's in that weed, and they freight it at top speed down to the South Island mussel farms. It's big money - the rumour was one guy made $80,000 in a month."

Fisheries officer
Fisheries officer West Hill

West Hill patrolled Ninety Mile Beach, checking the catches of the half-dozen commercial fishing vessels that put out from distant Ahipara, checking the paua divers that come out from Kaitaia, and the bag limits of the non-commercial surf-casters who set up anywhere along the beach. Or, he was turning his radar onto the big trawlers that came up from the south, checking that regulation nautical mile between them and high water mark.

"And we guard the toheroas. They're about half way down the beach. It's prohibited to take them, but everyone does, and we catch them. A $500 fine. This beach - I love it. The way the trees come down to the edge of the dunes. The wild horses. They've been out today, I've seen their hoof-prints on the sand. Fishing - you can get snapper, kahawai, mullet ... And in February, there's the fishing contest. That's a big one - $50,000 first prize, maybe 1000 anglers up here then, and you can win a vehicle as well."

He said goodbye, and I gave up for the day. The sky looked threatening and after I'd found a campsite upstream, I hammered extra lengths of wood around the tent. That night I awoke in total blackness. The rain, that had been pleasantly tack-tack-tacking on the fly when I went to sleep was belting against it now. The tent bucked and heaved, and the wind became more and more violent. I packed up my gear. The jerking tent floor knocked over the candle lantern - its flame enclosed against any contact with flammable material, but not entirely enclosed - and I had a brief moment of realising how easily, if this were a real cyclonic wind, and one made certain key mistakes, the thin fabric that keeps us safe might just rip away. I fell asleep later and when I checked in the morning, not a single tent-peg had been extracted or even loosened by the storm. Darkness perhaps exaggerates fear. Only the Leki sticks - stuck in the ground outside because of the damage their steel tips could do to the tent floor and now fallen over each other like exhausted children - gave any evidence of a rough night.