Quintin Mackinnon aka Ray Willett reaches the pass that bares his name and opened the way for the Milford Track.

The world famous Milford Track is described as "the finest walk in the world". Neil Ratley laces up his tramping boots to take part in the heritage walk celebrating 125 years of tourism on the Great Walk.

I'm treading in the snow-moulded boot prints of an explorer who passed this way 125 years ago. A mist sits on the mountain pass named after the man I am following. For a brief instant a gust of wind rustles the alpine tussock and parts the white curtain revealing a glimpse of the valley far below.

On October 17, 1888, Quinton Mackinnon and Earnest Mitchell, under instructions from the government of the day to find an overland tourist route to Milford Sound, discovered and crossed the mountains separating Te Anau from the coast.

Mackinnon Pass is the highest point on the Milford Track at 1154m.

The Mackinnon I am following is actually Te Anau identity and former Milford Track guide Ray Willett.

The real Quintin Mackinnon disappeared on Lake Te Anau in 1892. The lake was searched and Mackinnon's wrecked boat discovered but his body was never found - he is presumed to have drowned. A small iron cross sits on a rock in Lake Te Anau marking the site of the wreck.

"Quintin was reputed to be a big drinker and wore heavy boots. The combination of both probably sent him to the bottom of the lake if his boat struck trouble, " Willett reflects.

Mackinnon is just one of several historical figures closely associated with the Milford Track who I have joined for the track's 125th anniversary celebrations. Joining "Mackinnon" is artist- explorer Samuel Morton, who is believed to have crossed the pass before Mackinnon and Mitchell while he painted the dramatic Fiordland landscape.

The man wearing Morton's boots, braces and beret, Department of Conservation tracks and heritage ranger Ken Bradley, says Mackinnon opened up the pass but Morton walked it six years before.

On the pass, mist shrouds our group of 35 trampers - made up of guides, DOC staff, iwi representatives, members of the public and a Government minister. We gather beneath a stone cairn dedicated to Mackinnon and acknowledge the efforts of those who came before us while chasing curious keas from our packs.

My expedition began two days before, much like it did for the tourists Mackinnon guided from Te Anau through to Milford Sound in the late 19th century. A boat from Te Anau Downs carries us up to the head of Lake Te Anau and the Clinton Valley. There is a gentle amble beneath beech trees before we reach Glade House nestled beneath the imposing Dore Pass. The gin clear waters of the Clinton River reflect the surrounding mountains. Red beech trees reach skyward, and a wetland provides the habitat for less imposing flora.

As night slips down the mountain walls and envelops Clinton Hut we hear about the ancient people who explored and discovered the glacial carved valleys, crags and mighty waterfalls centuries before any intrepid European explorers passed this way. The Milford Track was an ancient pathway for Maori in Southland (Murihiku).

Ngai Tahu representative Dean Whaanga takes us back to a time when his ancestors used the Milford Track. The cool southern climate meant the Maori in Murihiku could not rely on cultivating food and travelled to take advantage of seasonal sources of food. Legends, place names and artefacts provide evidence Maori crossed Omanui (Mackinnon Pass) and entered Piopiotahi (Milford Sound).

Fiordland's lush green forests were filled with birds; its crystal waters harboured fish and isolated bays secreted valuable pounamu (greenstone). The Maori people used these natural resources to survive and trade, Whaanga says.

The sun burns away the early morning mist nestling in the valley. Along the banks of the Clinton River the foliage forms a kaleidoscopic corridor of green. Beards of lichen, mosses and ferns hang from gnarled and twisted tree branches.

It feels like old and wisened men are watching me. The screech of kaka, and the birdsong of bellbirds hidden behind the curtain of leaves punctuate the crisp air.

It's a gentle climb to the source of the Clinton River, Lake Mintaro. In places I am forced to scramble across the physical scars Mother Nature has slashed into the track. Swathes of forest have been torn from their roots by avalanches leaving behind a river of rocks and boulders to ford.

Long-time track guide Hamish Angus has spent the winter working on the Milford Road Avalanche Control Programme. He says avalanches are common in Fiordland and the Milford Track is subject to strict monitoring.

With Angus' words still ringing in my ears, a roar reverberates from high on the mountain. Several of us stand staring as a cascade of snow and rocks tumble down. It is not long before the mountain is silent again and we push on to the Mintaro Hut for the night.

It is a cold morning and pockets of snow sit on the ground. The thundering blades of a helicopter scare off several kea before they can pilfer our readied packs.

The people in charge of getting us safely over Mackinnon Pass, lead guides Bradley and Angus, are making a reconnaissance flight to assess the avalanche risk on the pass. If it's decided the risk on a section of the track is too great a helicopter is used to fly trampers to a safe spot on the track, Bradley explains. We are given the all clear to make for the pass on foot.

The old forest growth falls away and is replaced by low-lying alpine plants as we zigzag our way up the mountain. Above the bushline, tussock protrudes from the white carpet of snow while alpine daisies and buttercups brave the cold.

Nearing the pass, Mackinnon taps me on the shoulder and asks me to hold his walking stick while he changes out of his modern tramping gear and into something more appropriate for the occasion. He laces up his hobnailed boots and wraps himself into his woollen coat and trousers.

On the snow-covered saddle Mt Hart rises to my left and Mt Balloon to my right but I can only feel their looming presence beneath the thick misty blanket. After Mackinnon makes a speech celebrating his achievement 125 years before, our party heads for the sanctuary of the Pass Shelter. Conditions prove too dangerous for the descent, with the steep slopes of Mt Balloon considered an avalanche risk.

In groups of five, we are flown by helicopter off the saddle out of the cloudy mist and down in to the liquid mist of Sutherland Falls. At the base of the 580m falls, it feels like I'm standing in a raging storm. The force of the water cascading down the sheer rock face creates a whirlwind of cold air and moisture. The falls, believed to be the highest in New Zealand, are named after Donald Sutherland, who in 1880 spotted a distant flash of water through the treetops while exploring from his camp at Milford Sound.

Getting drenched by the powerful Sutherland Falls requires a short detour off the Milford Track. For the past year the sidetrack has been closed because of a large rockfall triggered by heavy rain. However, one of my tramping companions, Minister of Conservation Dr Nick Smith, officially opens the new track as part of 125th anniversary walk.

Following the Arthur River on the approach to Dumpling Hut the youngest member of the tramping party, 9-year-old Lachlan Falley from Australia, spies a pair of rare blue ducks ( whio). Paddling against the current the waterfowl dip their heads under the fast flowing water and feed on small invertebrates. At the hut, Smith says one of the highlights of the walk was seeing endangered species - such as the whio and brown teal (pateke). The recovery of these birds is the success story to come out of all the hard work being done by DOC, he says.

When I set off on my last day on the "finest walk in the world", I step back to April 1965, a time when the Milford Track and hut facilities were controlled by the Tourist Hotel Corporation and independent trampers were not permitted to walk the track. Walking with me are Robyn and John Armstrong, who, as members of the Otago Tramping Club, nearly 50 years ago were among 28 "revolutionaries" who decided the track should not be out of reach for ordinary Kiwis and international visitors.

The Armstrongs and the rest of the Otago Tramping Club's "Freedom Walk" paved the way for the opening of the track to independent walkers.

MacKay Falls appears like a landscape painting. The vivid greens and blues are still freshly glistening on the canvas. Alongside the Arthur River and Lake Ada I hug rock cuttings blasted and hand cut by labourers when the track was first constructed. At Giant Gate Falls, the water gushes into a pool of shimmering turquoise.

My final steps lead to Milford Sound and the end of my time on the Milford Track 125 years after Mackinnon opened it up for tourists. Today the track is more accessible than the inland route early Maori followed to the coast or the path Mackinnon carved out for the first tourists. But, there is no doubt the forest, mountains, valleys, rivers and waterfalls remain the same for my eyes as they did for all of those who have walked the Milford Track through the centuries.