However, the flight proved to be uneventful. Beneath us the Makgadikgadi Pans (dried lake beds), including the single largest pan in the world, shimmered in the heat, their boundaries blurred by mirages that turned the horizon to liquid.
But then a sinuous snake of blue appeared, a river with its surface flashing blindingly in the relentless sunlight. Its banks were flushed with green where trees were flourishing near the life-giving moisture.
I was about to ask the pilot if this was the supposedly dry Boteti River when my daughter, who was sitting beside the pilot, made a grab for a sick bag. A minute later she was demanding reinforcements from our seat pockets.
Undistracted the pilot flew on, preparing to land on a single dirt runway in what seemed to be the middle of nowhere.
We landed perfectly, if not exactly fragrantly, and came to a halt beside a lone Land Rover parked at the end of the runway.
Rachel, who hadn't been travel sick since she was about two years old, was mortified but the pilot seemed unconcerned. (Our pilot on the return journey told us that passengers were quite regularly sick — but not always as relatively tidily as Rachel: "Had it all over the controls, even me," he said cheerfully.
Patrick our guide then loaded us into his Jeep and we headed off into the scrubby wilderness, where twisted, gnarled bushes were some of the only plants surviving among what was largely tracts of sand.
Apart from a few cattle glimpsed through the undergrowth, there was no other living thing to be seen — what were we doing here?
And then we arrived at our lodge, Leroo La Tau, where the husband and wife managers and other staff were on hand to greet us with warm face towels and cold drinks.
They led us into the main lodge building, but we didn't get very far — we were immobilised, gobsmacked by the view.
The lodge is perched on a cliff about 10 metres above the Boteti River. In front of us the deep blue river stretched 30-40 metres to the far bank.
"But there's water in it," I blurted out.
The managers sighed.
"Are the agents still saying it's dry,? they said resignedly.
"We keep trying to tell them."
We three were the only guests — there was a chalet for Derek and me and next door one for Rachel. The entire front wall of the bedroom and of the beautiful bathroom with its massive walk-in shower was made of glass and a deck stretched the length of the bedroom giving an even closer view of the river. It was without doubt the most stunning view from any room we'd stayed in in Africa (and the room itself was superb).
We'd been invited to gather on the terrace for afternoon tea where the cook was proffering large slices of orange syrup cake. All three of us had decided already that two nights here were perhaps not enough.
It was about now we heard a strange high-pitched barking from across the river. The staff were looking at us expectantly... unlike us they knew what was about to unfold.
Through the trees on the far bank came a line of zebra, at first in single file, then more and more animals began threading their way through the undergrowth, fanning out as they reached the water.
Youngsters bucked and frolicked as they came down the sandy banks, all the time accompanied by a cacophony of zebra barking.
The Boteti River forms one of the boundaries of the Makgadikgadi Pans and Nxai Pan national parks, the latter of which is home to one of the largest populations of zebra in Africa.
We sat, enthralled, our cake suspended in midair. Then the wildebeest, with their shaggy manes and weirdly humped shoulders, started to caper down to the river as well.
During the late afternoon hours and before a brief but glorious sunset, what seemed like thousands of zebra visited the river. It was one of the most magnificent sights we'd experienced in Africa.
Early the next morning, Patrick collected us to make the short journey upriver to where a small flat-bottomed boat was waiting for us.
We crossed into the national park from here — gliding past African fish eagles perched in the trees — and then paused mid-stream to watch four elephants, (young bachelors who had been forced out of their family group) loping down the bank to the water's edge. They drank long and deep and then moved to stand in the shade, motionless apart from the languid flapping of their huge ears.
Despite the abundant array of meals on the hoof in the park, lions and other predators totally eluded us during our safaris.
The park is surrounded by an impressive wire fence which is designed to keep wildlife and domestic animals apart. It is also supposed to stop lions from preying on cattle, which are a far easier target than their usual fare.
However, we saw several spots where the big cats had simply tunnelled their way underneath and their absence rather implied they were feasting on steak takeaways rather than perusing zebra.
However, the sight of giraffe, wildebeest and zebra drinking together at a pool where the river had overflowed and the prolific birdlife in the park, which Patrick was astonishingly adept at spotting, more than made up for this.
And there are not too many places where one can lie in bed (or even stand in the shower) and watch zebra and elephant wandering past.
We could relax about not seeing lions and other big cats here because we'd visited a number of parks — this is one way to ensure you do see a variety of wildlife in Africa — don't put all your safari eggs in one basket — try to budget for several countries and a range of different parks within them. Our stay at Leroo La Tau was entirely at our own expense.
