The Zambezi River begins its run ever so gently in Zambia, and courses through Zimbabwe and Mozambique before flowing into the Indian Ocean some 2,700 kilometers (1,678 miles) away.
Along the way, it takes some surprising, dramatic, beautiful, and unexpected turns.
In Zimbabwe at the Zambia border it puts on its major show.
Here, where the earth cracks open in a mile-wide gap, the gentle river turns savage and plummets over a 330-foot precipice in a never-ending, deafening roar.
Plumes of silvery-white mist shoot hundreds of feet in the air before falling softly on the fig and mahogany trees and wild date palms below. On sunny days, double rainbows in broad, brilliant, moire ribbons arch over the falls, bringing a touch of Edenesque beauty to the perpetual rain forest the mist creates.
Intrepid tourists donning rented ponchos and juggling umbrellas and cameras flock to these raging falls - considered one of the seven natural wonders of the world
"Mosi-oa-Tunya" - the Smoke that Thunders - is its African name. We know it as Victoria Falls, christened by its British discoverer, David Livingston, who named it for his beloved English queen.
To most tourists (and the troop of sensible baboons who live in the rain forest along the banks of the falls) this bucolic panorama is quite satisfying enough.
But for the adventuresome (to use a euphemism), Shearwater Adventures, one of several rafting companies in the area, has something a little more challenging in store.
"Shear-adventure, Shear-beauty, Shear-wonder, Shear-excitement" the company advertises. (Note that "Shear-terror" is conveniently omitted.)
About 30 enthusiastic, somewhat foolish and naive stalwarts met at 7:45 a.m. at a nearby motel to be briefed by Shearwater on the day's events.
You begin to pick up clues as to what's in store, when, after a lecture on the condition of the rapids, and safety precautions, you are requested to sign a release form (something about notifying your next of kin if, ...well, you get the picture.)
"Oh, and if you're Australian, you can sign your name with an 'X', that's OK," our lecturer quipped.
The rapids here are class 5, we were told. Class 6 rapids are not navigable by humans.
Major rapids on the river have all been given names by the guides; Overland Truck Eater, The Terminator, Silent Assassin, and if those don't make you wish you'd rather be back home soaking in a Jacuzzi, there's that perennial favorite - the Gnashing Jaws of Death, thank you very much.
We were also issued a three-foot-long strand of string. "Now tie one end to the bridge of your sunglasses and the other through a button hole on your shirt. You wouldn't want you to lose your glasses, would you?"
Call me chicken, but I was far more concerned with holding onto my life.
We were then all boosted aboard a high, wide, open truck and bounced our way over dirt roads to the top of a gorge, several miles down from Vic Falls.
Here we were fitted with blue crash helmets and yellow life jackets before scampering down into the base of the canyon like so many lemmings with a death wish.
Six 18-foot, black rubber rafts bobbing benignly in a shaded, sheltered lagoon waited for us below.
"Welcome aboard," said our grinning guide from Malawi. "My name's 'Hippo.' "
Before we boarded, all cameras (and worst of all, my pen and notebook) were collected by a photographer who was going to precede us down the river. He stuffed them in a Ziploc bag, and tucked them into his kayak. "Now the most important thing is to smile for the camera" he said, aiming his camcorder in our direction. At this point, we could all manage a nervous smile.
Hippo helped us to our slippery "seats" while his younger assistant, Levy, gave us some tips on raft procedure.
These amounted to instructions on how to throw your body from side to side in a somewhat futile attempt to "steer" our raft through the rapids.
And off we plunged. We hit the first rapid head on, were engulfed in a wall of water, and came up sputtering, hearts pounding, exhilarated, and drenched to the bone. Hippo forgot to tell us that it doesn't do a bit of good to scream, you only get a mouthful of Zambezi.
And so it went for 11 miles tossed, spun, and pounded by this capricious river that doesn't take kindly to strangers.
In between being slugged by the Terminator, doused by the Silent Assassin, and slammed by the Overland Truck Eater, we'd pull into a quiet eddy to catch our breath, wring out our socks, and absorb the extraordinary beauty that sandwiched us between cliffs of black basalt. All the while the dazzling sun threw diamonds on the dark water.
Overhead, fish eagles and black storks hung suspended in the powder-blue sky. Only a few grinning crocodiles that lay basking on nearby rocks, and the next rapid, seemed threatening.
Those happy crocodiles, Hippo informed us, made it over Victoria Falls intact as youngsters. The falls are not so kind to large crocs, with their weighty body mass.
After two-and-a-half hours of wash, rinse, and spin-dry cycles - and everything else the Zambezi could throw at us - our rafts were pulled safely on the rocks.
And if that wasn't brutal enough, now comes the hardest part: There's only one way out of the gorge, and it's 750 feet straight up! The equivalent of climbing a 70-story building.
For almost an hour we dragged, pulled, and hauled ourselves over rocks, roots, and narrow trails, panting and gasping before finally clawing our way to the top.
In retrospect, the trip down the Zambezi seemed a bit like driving your automobile through a car wash, (with the added threat of being eaten by crocodiles.)