Scrambling up on the rocky outcrop was not easy. The stones were loose and crumbling, the bushes thick and unyielding. Most of all, I was alone. I kept telling myself that: I'm alone on a 4,000m mountain plateau in the heart of Africa, and I have wandered off the path.
At the top, I sat down on a flat rock and enjoyed the spectacular view across the Aberdare national park. The sky was a miraculous deep blue, broken only by the silhouette of an Augur buzzard cruising along some invisible air current. I scanned the grasslands below: no elephants or lions to be seen.
For many years, most tourism in Africa has had a very simple arc: you drive in a 4x4, bouncing up a track, then sit and watch a group of animals. Then you do it again. It is a model that evolved out of the colonial-era hunting experience, the guns being replaced with cameras (though not entirely – big game hunting is still going on).
But Africa is changing, and fast. Old ways are being dropped. And nowhere more so than in Kenya, a country with double-digit economic growth and an expanding population with rising economic expectations. Change has also come to the Aberdares, a mountain massif 50 miles north of Nairobi. In particular there are new campsites and nature trails that allow visitors to do what was previously unthinkable: walk for several days across a reserve where lions, elephants and buffalo roam. For anyone who has known the sheltered world of guides and 4x4s, this is a revolution.
I was in the Aberdares as part of a team making a film about urgent botanical work going on in Kenya, but I was determined to sample the delights of walking through the bush. Fortunately, in the higher altitudes of the range, the more dangerous animals are very rarely seen; they prefer to stay in the forests below. I had left the team rhapsodising over some strange tiny plants in a mountain stream and taken off along the ridge, heading south. There was a clear path, but I had found the lookout hill irresistible.
Although the primary draw of Kenya is almost always its wildlife, in the Aberdares the plant life runs it a close second. East Africa has a handful of isolated high-altitude ranges, including Kilimanjaro, Mount Kenya and Mount Eldoret. On each of these a unique vegetation has evolved to cope with blistering daytime sun and freezing night-time temperatures.
That evolutionary challenge has resulted in some bizarre and wonderful creations: four-metre-tall groundsel trees whose leaves ooze an anti-freeze solution, and shaggy lobelia trees standing like Easter Island statues in the grassy slopes. With global temperatures rising, these giants are retreating up the mountains and are now on the very tops, with nowhere to go. Only the previous day we had stopped our Land Rover a short distance below the summit to collect seed from a type of wild tomato, a species only discovered a year before but already endangered. With an estimated one-in-four plant species now threatened with extinction, this environment is at the front line of the battle to save genetic material that could be vital to agriculture and medicine.
I left my secluded mountaintop and clambered back down to the path, then wandered on into a sunny dell where the giant groundsels were clustered together. In Europe, the plant is a common weed and these trees had an oddly familiar look. It was like walking through my own untended allotment after eating the wrong kind of mushrooms.
The path reached a ridge line and for the next hour I had magnificent views all the way to Mount Kenya, 50 miles away. When Europeans first saw this peak it was a snow-capped wonder, but now there was no sign of ice at all.