The buffalo bull had been killed in the night. Now, only the horned head and a black bag of bones remained at the scene of the crime; but the butchers, the Kutandala lion pride, were not far away, sleeping off their blowout feast in the thorny thickets of North Luangwa National Park.

We went looking for them, walking quietly through the thick bush, talking in whispers. In front was Tryson Nkhoma, our armed ranger; then came Rod Tether, my guide; then me.

Suddenly, Tryson froze. Rod pointed. And there were the lions — an adult lioness and three young males with rag-tag manes, resting on the far side of a clearing. We moved closer, more slowly now, approaching obliquely until no more than 100ft of open ground lay between us, and it occurred to me that a lion could cover that distance in about three seconds flat.

For maybe five minutes, we stood there. We watched them and they watched us, until eventually the three youngsters switched off. One by one, their heads dropped and they began to doze, panting in the windless heat. But not so the lioness. Her whole body language said “Don’t mess with me”, and even when we backed away, I could still feel her pale eyes upon me, as if she was looking deep into my soul.

WALKING IN lion country is a good way to increase your attention span; and when it comes to foot safaris, there is nowhere better than Zambia. After all, this is the country where the old-fashioned, Dr Livingstone-style safari was reinvented.

How fast the world has moved on since Livingstone died here in Chitambo in the Bangweulu Wetlands in 1873. Today’s travellers come prepared for everything Africa can throw at them. They pop anti- malaria pills, zoom in by plane, hit the bush in padded Toyota Land Cruisers and chill out in five-star luxury lodges.

Yet still there are those who hanker for a more down-to-earth safari experience — one that brings you face to face with nature on level terms — showering under the stars, travelling on foot, the way it used to be. And that is what Zambia offers. It is unexpurgated Africa: wild, vast and hugely underrated. Thirty per cent of the country is national parkland, and while neighbouring countries have been rocked by turmoil, Zambia has been quietly ticking along, greeting visitors with the warm est welcome south of the equator.

Its most celebrated slice of wildlife real estate is the Luangwa Valley, an immense offshoot of the Great Rift Valley. Through it runs the Luangwa River, coiling for 500 miles past sand bars as big as Cornish beaches and riverine forests of great blowsy trees. During the rains, it bursts its banks; in the dry season, it flows sluggishly but never fails to provide water for the hippos — 40 for every mile of river — and the monster crocodiles that bask on its banks with jaws agape.

Most visitors stay in South Luangwa, a national park the size of Wales. There is a score of bush camps and safari lodges here, but tourism remains low-key and low- impact, with the accent on walking safaris, accompanied by some of Africa’s most bush-savvy guides.

Foremost among them is Robin Pope. I first met him in the late 1970s when he was a young protégé of the late Norman Carr, the game warden who pioneered the concept of walking safaris right here in South Luangwa. Diffident, unassuming, quiet, in London he could pass for a librarian; but in Zambia, in his faded shorts and beaten-up, wide-brimmed bush hat, he is the consummate professional safari companion.

Pope’s camp, Tena Tena, is generally acknowledged to be the best in the valley. On one side is the Luangwa River, its banks echoing constantly to the bellowing of hippos. On the other is a small lagoon where, during my stay, I watched bushbuck and elephant come to drink; and once, in the small hours, I heard the hacksaw cough of a prowling leopard ripping through the darkness.

At Tena Tena they get up early, to walk while the air is still cool. As the sun rose, we passed a palm tree in which a pair of red-necked falcons were nesting, then cut across a dried-up oxbow lagoon, its bed pot-holed by the giant footprints of hippo and elephant. On the other side, Robin found fresh leopard tracks in the dust. Was this the cat that I had heard in the night?

We walked on, and soon the long grass had closed around us, tall enough to hide an elephant. This is what the Zambians call “adrenaline grass” — for obvious reasons — and I was reassured to see that Isaiah Nyrenda, our game scout, carried a .458 Parker-Hale rifle, whose bullets were the size of chipolatas and would, if required, stop a charging tusker. But such incidents are almost unheard of in the valley.

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