NO OTHER sound is as humbling as the low, deep-throated roar of a lion as it reverberates beneath vast, moon-lit African skies, across dusty, acacia-dotted plains and on through the worn, dark green canvas of a safari tent.
At first it sounds like a distant, unbaffled truck engine, fading in and out with the wind, but then it seems too close, too sinuous to be man-made.
It is too throaty to be the thundering of a buffalo herd, or the charge of an elephant; too elastic in its slow, rolling cycle to involve metal. Elimination rather than recognition finally tells you it must be a lion.
''Simba,'' a Masai guard confirmed in reverent Swahili tones the following morning. ''Did you hear him last night?'' We had camped at Aruba Lodge in the 20,000-square-kilometre Tsavo National Park - the largest of Kenya's 31 national parks and game reserves - on our way from Mombasa on the Kenyan coast to Nairobi, the purple-tinged jacaranda city.
Earlier we paid our 450 Kenyan schillings (about HK$100) entrance fee, headed into the park in our hired four-wheel-drive Suzuki and instantly began to experience the real Africa.
Giraffe catwalked amid the trees elegantly - like hip-swinging Paris tarts; ostrich motored across our path, the black and white males outshining their mousy-coloured mates, and warthog, their half-manes flowing in the wind, thrust their tails in the airlike car aerials and trotted off, tusks at the ready, looking for all the world like extras from a Mad Max set.