South Luangwa packs hippos more tightly than almost anywhere on Earth — surveys along its stretch of the Luangwa River have counted around forty animals to every kilometre of water. The park covers 9,050 square kilometres of the Luangwa Valley, the southern arm of the East African Rift, and the river is its engine: each flood season it bites into its outer bends, cuts a new channel and abandons the old, leaving oxbow lagoons that hold the animals once the rains stop. Hemmed in by the Muchinga Escarpment, the valley grew a wildlife of its own — leopards at some of the highest densities recorded in southern Africa, and Thornicroft's giraffe, which lives here and nowhere else, alongside Cookson's wildebeest and Crawshay's zebra. In 1950 the conservationist Norman Carr persuaded Senior Chief Nsefu to set aside tribal land as a reserve, then opened the first camp in the country where visitors came to photograph animals rather than shoot them. The walking safari he built here became the valley's signature; the reserve became a national park in 1972.
On foot, behind an armed scout and a tracker, the valley arrives at ground level — fresh spoor in the sand, a vervet monkey's alarm call, the tunnel an elephant has crushed through the mopane. Night drives, legal in Zambia's parks and rare elsewhere, are the surest way to watch a leopard hunt. From September the falling river lays its clay banks bare, and thousands of southern carmine bee-eaters burrow nests into the cliffs and turn them scarlet. In January the valley flips: the rains push the Luangwa over its banks, ebony groves stand in water, yellow-billed storks crowd a breeding colony in the Nsefu sector, and boats go where no vehicle can. Most camps close as the tracks turn to grease; the few that stay open trade the game drive for a paddle through flooded lagoons.