Until recently Solio never figured on the tourist map because there was nowhere to stay inside the reserve. But that all changed in August with the opening of Solio Safari Lodge. Run by Tanya and Mikey Carr-Hartley, whose family have been involved in the Kenyan wildlife scene for three generations, it offers visitors the same high standards of comfort provided at Sasaab, their flagship lodge in Samburu.
Solio's five guest cottages are the epitome of safari-chic, combining traditional thatched roofs with floor-to-ceiling windows and spacious bathrooms with free-standing ceramic tubs.
At 7,000ft above sea level nights are cold, so every evening when you return after sundown in the bush you find your room steward has lit a blazing acacia-wood fire. You can even have a fire in the bathroom if you wish.
From the moment I arrived it was clear that Solio is a bird watcher's dream. A long-crested eagle with chocolate plumage and yellow talons glared from a dead tree.
Montagu's harriers sailed on outstretched wings over the lion-coloured grasslands and a pair of tame crowned cranes (known, inevitably, as Will and Kate), engaged in a graceful courtship dance on the lawn.
But the rhinos are the main attraction and at Solio they are hard to miss.
Their middens (rhinos are creatures of habit) are everywhere, marking where males had laid claim to their territories; and at one point on my first morning game drive, where the jasmine-scented carissia bush gave way to open plains, I had more than 20 rhinos in full view at the same time – including the unmistakable Otoro.
The only cloud on the horizon is the surge in poaching fuelled by China's hunger for rhino horn. Used in traditional Chinese medicine, rhino horns are worth more than their weight in gold and are currently changing hands at up to $60,000 (£37,484) a kilo. With thousands of Chinese at work in Kenya on new roads and other development projects, Solio has become a prime target for poachers and the reserve lost at least 12 rhinos last year.
Visitors are safe because the poachers operate at night when tourists are safely tucked up in bed, but the rhinos are vulnerable in spite of round-the-clock foot patrols by armed rangers. To beef up security, the 30 miles of electric fencing at Solio is being upgraded and fitted with an automated intruder alarm system that will cost at least US $500,000 (£312,316).
Meanwhile, the Kenya Wildlife Service is planning to translocate a dozen black rhinos to the Aberdare national park, just a 20-minute drive away.
Unlike the rolling savannahs and flat-topped thorn trees of lowland Kenya the Aberdares is a mountain world whose deep ravines and dense cloud forest provide a refuge for all kinds of animals including some seldom seen elsewhere. The bongo – a shy chestnut antelope the size of a pony – lingers like a legend in the bamboo groves. Melanistic serval cats roam the alpine moorlands above the tree line, and the giant forest hog – 500lbs of pork encased in a bristly black hide – snuffles about in the leaf litter.
"This is the only place in the world where you are ever likely to see a black leopard," says Colin Church, my guide in the Aberdares, who is more concerned about the fate of the park's black rhinos.
Church's love affair with the Aberdares began when he was 14 and on a trout fishing expedition during the Mau Mau uprising. Today this former journalist and Nairobi PR guru heads the management committee of Rhino Ark (www.rhinoark.org), the organisation responsible for the electric fence that now protects the park.
The first post was sunk in 1988, a time when poachers were driving the black rhino to extinction, and the idea was to protect the park's eastern salient which lies right up against some of Kenya's most fertile farmlands.
That was when Ken Kuhle, a qualified engineer with a bee in his bonnet about conservation, kick-started the Rhino Charge, a rip-roaring, off-road four-wheel racing event that now raises more than $1 million (£624,500) a year.
A 7ft-tall electric fence seemed like the most effective way of keeping the wildlife safe. At the same time it prevented elephants breaking out on crop-destroying sprees, and the idea was so popular with the local communities that what began as a crazy dream to ring-fence the rhino ended up by saving a whole mountain range. When completed in March last year it encircled 2,000 sq km (772 sq miles) of indigenous forest and high alpine moors, including the entire Aberdare national park.
"The sheer size of the task was mind-blowing," says Church. "If you were able to unravel all the wire cable strung around the Aberdares it would stretch from Nairobi to London." Its importance cannot be overestimated – not for the Aberdare rhinos of which only a handful remain – but in protecting the mountains that catch the rains. With its 4,000m (13,123ft) summits and mist-shrouded forests the Aberdare range is a giant sponge feeding five of Kenya's major rivers.
One in three Kenyans depends upon it for power and water, including the entire city of Nairobi. No wonder Church calls it "one of our most precious water towers". The result has been a win-win situation for everyone except the illegal loggers, land-grabbers, grazers and poachers. The park's wildlife enjoys greater protection and the 40,000 families living within a mile of the fence no longer have to put up with crop-raiding elephants.
Most visitors to the Aberdare park end up at one of its two forest lodges – Treetops and the Ark. Both are situated in the eastern salient, a beautiful area of flowering chestnuts, lofty cedars and podocarpus trees with massive fluted trunks.
Treetops, founded in 1932, is the oldest tourist lodge in Kenya, and in 1952 it became the world's most famous tree house when Princess Elizabeth learnt of the death of her father while she was there on an official visit. Jim Corbett, the legendary hunter who was resident at the time, recorded the event in the Treetops logbook. "For the first time in the history of the world," he wrote, "a young girl climbed into the tree as a princess and climbed down next day as a queen."
The Ark may lack the history but it lies deeper in the forest, a triple-decker, cedar-clad ship of the forest that has come to rest in a marshy glade 7,500ft above the sea. There is no need to go jolting around in the bush when you stay at this snug redoubt. Instead the animals come to you – lured by a natural salt lick.
Darkness falls with a shrilling of frogs as the waterhole, with its ghostly herons, is transformed into a floodlit arena, a theatre in which all kinds of dramas are enacted nightly. Elephant, buffalo and giant forest hog all put in a regular appearance and there is a buzzer in your room to wake you if nocturnal superstars such as leopards put in an appearance.
Beyond the salient, winding trails climb higher into the park beneath centuries-old hagenia trees dripping with moss and lichens. Wooded ravines echo to the hiss of 900ft waterfalls; and when at last you emerge from the bamboo zone it is to find yourself high in the clouds, where the summit of Oldoinyo La Satima broods over a desolation of sombre moorlands.
You could almost think you were in Scotland; perhaps somewhere in the high-tops above Ullapool or Loch Maree. And then you notice the giant lobelias, the clumps of heather as tall as your head, and a herd of eland trotting over the skyline and know you are standing on the roof of Africa.
Brian Jackman’s visit to Solio and the Aberdares was arranged by Gamewatchers Safaris (call 0870 471 7122 or email firstname.lastname@example.org).
Gamewatchers can arrange a week’s safari in Kenya with one night at the new tented camp in Nairobi National Park, one night at The Ark, two nights at Solio and two nights at Sasaab in Samburu. Prices (excluding flights to Nairobi) are from £2,440 for each of two persons travelling together and include all local flights and transfers.