I was camped, alone, on the Limpopo river, staring into the shadows away from the dying embers of my fire. I strained my ears in the eerie silence around me, scarcely breathing as I aimed my microphone towards the sound I had heard moments before.

Then it came again, tearing through the silence like a gigantic wood saw. I snapped on the Nagra and watched its recording needle dance to the waves of sound. A baboon barked hysterically, followed by the others in his troop, and then a battalion of rock dassies bellowed in unison, almost drowning the baboons in their eagerness to warn each other about the presence of the leopard.

The sounds died almost as soon as they had erupted, and I leant back in my chair feeling a warm glow of satisfaction. I had been here for some weeks, becoming increasingly introspective and preoccupied. I had lost track of the days I had spent in this place; I wasn't even sure what month it was, nor did I care.

Today I had seen an almost perfect Massospondylus, a baby one which had fallen on its back and died 200 million years ago. Had it fallen from a cliff or merely been caught in mud? Had it's mother abandoned it or had she tried to save him? Had it died in silence or squealing in fear? The stone skeleton was lying intact where it had fallen; not a bone displaced. How could one worry about what day of the week it was under such circumstances?

The sandstone loomed up around my solitary camp, wrought by the elements into fantastic shapes. To the north a monk could clearly be seen leaning over his lectern and to the west the bearded face of a man, 20 metres high from mouth to forehead, stared from the cliff face, his eyes sunk in shadow. The trunk of a rock fig shining silver in the moonlight clawed up a rock face and I could just make out the shape of a hyrax in its branches, feeding quickly, braving the possibility of an attack from an eagle owl in it's eagerness for the succulent leaves.

I stumbled upon Sentinel ranch, a 32,000 hectare estate bordering the Limpopo river some 60 kilometres west of Beit bridge in Zimbabwe, almost by accident. I was looking for a location to film a documentary about rock hyrax and a friend of the Bristow family, who own the ranch, described a 'super-abundance' of these little mammals, together with a full range of their predators; Black eagles, leopards, caracals, black mambas, and pythons.

"Sentinel is a pure wildlife area," I was told. "No cattle, no crops; it's just like a National park, except that you'll have the whole thing to yourself". I was somewhat sceptical about this. Owners of game ranches often imagine they can mix domestic stock with wild animals. The result is a disappointing mixture of poorly adapted bovines rubbing shoulders with wild plains game, and of course no hyenas, no cheetah, no painted dogs, no leopards and certainly no lions are allowed! Buffalo might pass on foot and mouth disease; elephants and rhino might kill the cattle at water holes, so they have to be forbidden as well. The result is a poor representation of mammal species and a weakened gene pool because the plains game have none of their usual predators to weed out the weak. An Africa without predators is not what visitors come to see.

The Sentinel owners abandoned cattle many years ago and resolved to use the land entirely as a wildlife resource. Most of the plains beyond the Limpopo escarpment have been designated as a hunting area, but 12,000 hectares adjoining the river are reserved exclusively for 'Eco tourism'. Not that the place is swamped with tourists. So few people have heard of it. Victoria Falls, Hwange, Lake Kariba; these names have a familiar ring when a holiday in Zimbabwe is under consideration. But the Limpopo? Snatches of vaguely remembered Kipling doggerel about the "Great, grey, green, greasy Limpopo, all set about with fever trees" come to mind.

Visions of a filthy border post manned by obstructive customs officials swim before one's eyes. Who would want to go there? Beitbridge border post, 50km downstream, can be avoided altogether, and fever trees are one of the stark attractions of the river front, their trunks glowing a luminous green against the red sandstone.

Those few who have visited Sentinel tend to return. The area teems with impala, kudu, zebra, ostriches, wildebeest, eland, warthog, and elephants. Leopards, hyenas and even the occasional nomadic lion take full advantage of the opportunities offered by this abundance of prey. The bleached bones of victims litter theplains; wildebeest and kudu remains can be found high up among the rocks in seemingly impossible places, and scattered among them, embedded in rocks and exposed by the rare rainstorms, lie the bones of dinosaurs.

Sentinel has some of the world's richest fossil deposits, a veritable Jurassic park. To date, the remains of 28 dinosaurs have been found in the Limpopo valley. Most are of Massospondylus, a vegetarian measuring three to four metres from nose to tail tip, but there are also traces of a small carnivorous dinosaur, Syntarsus, which may have been covered with feathers as a protection against harsh desert temperatures. Most of the remains found on Sentinel are between 190 and 210 million years old.

The river itself bespeaks great antiquity; it was the great waterway of south central Africa long before the Zambezi was born. Indeed, the upstart Zambezi stole its waters, arrogantly claiming them and forming them into the greatest waterfall on earth, while the loser, the Limpopo, withered and died to a fraction of it's former glory.

Most geologists believe the headwaters of the Zambezi flowed south east through the Makgadikgadi depression in Botswana and then south to join the Limpopo system. Gentle movements of the earth's crust about two million years ago are thought to have cut off this flow into the Limpopo, resulting in a huge inland lake the remains of which include the Okavango Delta, the Chobe swamps and the Makgadikgadi salt pans. Spillage from this vast, shallow lake ran into the low lying area to the east, carving a new river valley which eventually became the Zambezi we know today.

All that remains of the Limpopo are eerie sandstone scarps and a river which now usually stops flowing altogether in the dry season, although that is mainly because of recent damming and irrigation in South Africa. It certainly flowed in historical times. Among the many bushmen paintings to be found throughout the area is a unique work of art in a green copper-based dye of a bottlenose fish swimming in a typical bottom feeding manner. This species would not have occurred without a perennial flow.

The sand in the riverbed is immensely deep, another indication of the great age of the river. Sentinel ranch draws its drinking water from 27 metres below the surface. Huge Sycamore figs line the banks, creating a dense forest canopy, but away from the river the land is a semi desert with the lowest rainfall in Zimbabwe.

Working in this curious area, I have gradually developed my own names for the weathered sandstone features: the Colosseum, the Amphitheatre, Disneyland, Leopard's rock, and so on.

Each evening I sit in some favourite place watching the antics of rock dassies as the sandstone glows a deep burnished red before the sun slips below the plains. Barking geckos start their peculiar 'yip yip' noises and if I am lucky I might see a kudu bull standing on a splinter of rock, his horns spiralled against the darkening sky. Soon the bat eared foxes, porcupines and arkvarks, springhares and caracals will come out to begin their nocturnal lives.

An intercontinental jet passes high overhead, it's contrail lit by the setting sun. I think about the people up there, ice tinkling in their cocktail glasses as they wait for their dinner to be served. For me they are part of another world, 200 million years away. I think, for now, I'd rather stay in the triassic.

Jan Teede is a professional photographer, freelance journalist and film-maker based in Harare. He and his wife have written two books, African Thunder, about Victoria Falls, and Zambezi River of the Gods.

Published in Travel Africa Edition Two: Winter 1997/8.Text is subject to Worldwide Copyright (c)