KEY POINTS:
Standing near the Huka Falls, you can feel the power of the Waikato River in the vibrations passing through your body.
Every second, 220,000 litres of water thunders through a channel just 15m wide and 10m deep. It's an awe-inspiring sight for the tourists, who arrive by the busload.
For many this place, just downstream from the Lake Taupo control gates, is effectively where New Zealand's longest river begins - even though Tuwharetoa iwi believe the Waikato can be traced all the way back to the base of Mt Ruapehu.
Not far on from the falls, the Aratiatia dam marks the beginning of the country's most developed hydroelectric power generation system. In all, 11 stations - including two geothermal, one coal and gas, and eight hydro-powered - line the river's banks.
Just past the dam, a joyride through the Nga-awapurua (Fuljames) rapids on a jetboat helps to reveal the incredible clarity of the river's icy blue contents. Rapids Jet driver Simon McLeod says the pristine water is due to a natural filtering system consisting of pumice and volcanic compounds.
"Forty-seven streams and rivers enter Lake Taupo, but just one river exits it," he proudly shouts as he approaches, at breakneck speed, the narrowest point in the river. The banks are about 150cm either side of the weaving boat.
About 20km downstream, a more serene attraction lies hidden in the river's valley between Rotorua and Taupo.
On the eastern embankment, the relatively undiscovered Orakei Korako is described by Lonely Planet as "possibly the best thermal area left in New Zealand and one of the finest in the world".
The river then carves west at Atiamuri, passing the isolated towns of Whakamaru and Mangakino. Cliffs of more than 100m rising high above the river give one a sense of driving around the South Island's west coast.
But at Whakamaru an array of enormous electricity pylons makes a sudden change. Like an intricate highway system, hundreds scar a beautiful landscape.
Farther north the river comes to rest at Lake Arapuni. The dam is nestled in a narrow, deep gorge and is surrounded by native bush.
Around the corner the river runs in to Lake Karapiro, passing alongside some of the world's most fertile farmland. Dairy farms are suddenly outnumbered by extravagant lifestyle blocks and attractive stud farms.
Just 6km upstream of Cambridge, Karapiro will host the World Rowing Championships in 2010.
By the time it reaches Hamilton, the Waikato is 13m above sea level, having undergone a 344m vertical descent since leaving Taupo.
Scores of rowers flock to the river for morning and evening training sessions. But the currents are tricky. Within city limits there have been five drownings in the river since 2000.
The water's green tinge is transformed to a muddy, thick, brown colour when it merges with the silt-laden Waipa River at Ngaruawahia. Farther on at Huntly, water temperatures reach up to 25C. The country's largest power station sucks up water for thermal generation, then pumps it all back.
The dark currents whirl past Rangiriri pa, scene of one of the most important battles of the New Zealand Wars. In 1863, Maori lost fewer lives (36) than the British (38), despite being outnumbered three-to-one.
Today, Maori fight to protect their food sources in the area, with eel being one of the most treasured delicacies. Commercial eeler Shane Hahn sells his catch to a Tainui-owned fishing business. He has worked on the river for 17 years and knows it intricately.
The natural ecosystem, such as swamps and wetlands, is being messed with in these parts and is the cause of the river's diminishing food stocks, he says.
At Mercer a few rusting vessels sit partly submerged on the western banks, reminding commuters on State Highway 1 of a bygone era in New Zealand transport.
Shipping pio-neer Caesar Roose is buried alongside the banks here. He began a river transport service between Port Waikato and Cambridge in 1915, and later began to trade throughout the region with a fleet of six vessels.
"My father used to work on his ships," says Tainui kuia Iti Rawiri, 84, as she sits at Te Awanarahi marae, a stone's throw from the river between Tuakau and Port Waikato.
"He was a [coal] stoker, and worked on the Rawhiti" (a 64m paddle steamer, the Rawhiti was the largest of all vessels to have graced the Waikato). Mrs Rawiri overlooks a large gathering at the annual pokai - an event staged by Tainui's Ngati Amaru in which the newly crowned King Tuheitia is being hosted.
Within Tainui these people are known as the "river people", and unsurprisingly Mrs Rawiri has lived her entire life on these banks.
As she explains the link between the mountain, river, marae and sea, she talks about the Waikato with the kind of affection normally reserved for close relatives.
"We believe it looks after us when we are sick. It's our healer. The taniwha is in there. When others die they become part of the river, and we pray to those people and they help us."
On December 3 a police convoy carrying Maori elders sprayed 10,000 litres of Waikato water on SH1 and SH2. The ceremony was to release the trapped spirits of people killed in road crashes.
Port Waikato marks the end of the journey, and the place has a lonely, deserted feel. Shallow in parts, the river at full tide is hundreds of metres wide. Its body seems exhausted and the Tasman Sea consumes it.
Early in the colonial era, this area bustled with activity. The sign on the dairy reveals trade in the tiny shop began in 1893.
Store proprietors Frog (Robert) and Fay Grigg moved to live here in the 1990s, citing lifestyle as the drawcard. The pace is slow and the people few but familiar.
Comedian Ewan Gilmour bowls up for some milk. Why does he retreat to these parts? "It's a bit more real. There are still true baches here, everything's still quite raw, it's still undiscovered."
It's also a hunter's paradise. Pig hunting, duck shooting and fishing are extremely popular. These days more surfers are making tracks out here to cut up the unoccupied waves.
Down the road, a handful of hermits are rumoured to have built homes on crown land, but nobody seems to mind. It's like going back in time 50 years.
