That’s where the famous Israeli raid took place,” says Steven, our travel representative, as we leave Entebbe’s new airport. He’s pointing to the old one: a collection of low buildings with a small control tower, still familiar from media coverage in 1976, when pro-Palestinian skyjackers were given refuge here while holding 100 Jewish passengers hostage, before Israeli commandos flew in for a triumphant rescue.

It’s a sign of the times that terrorism is on your mind when visiting a country, but I feel haunted by another event in Uganda. In 1999, eight tourists, visiting Bwindi Impenetrable National Park to view the mountain gorillas, were murdered by Rwandan soldiers from over the border. It’s thought they wanted to harm tourism, and they succeeded for a while. My partner, Greg, and I are wildlife fanatics, and the gorillas have always been high on our wish-list, but we were so shocked by that incident — made worse because the violence was directed at nature-lovers — we cancelled all plans. Now, we’re assured it’s safe again.

Before the gorillas, we’re going to see some of their smaller relatives, chimpanzees. We board a motorboat and set off across Lake Victoria, headed for Ngamba Island, where there’s a chimp sanctuary established by the Jane Goodall Institute.

We’re met by the supervisor, a tall, gentle man with a passion for the animals that is infectious. His name sounds like Julius Caesar’s best friend, but turns out to be Macanthony. He points to a post on the shoreline, labelled “Emergency Assembly Point”. The chimps are separated from us by an electrified fence, but the current has been known to fail and they have been known to break loose. If so, we should run to the post, and, if they keep coming, jump into the lake — they can’t abide water.

The Ngamba chimps were rescued as infants while being smuggled through customs for use as pets or bush meat. Some were found suffocating in small boxes, baskets, even briefcases. These orphans have now formed themselves into two large groups. The island vegetation can’t fully sustain them, so they’re fed daily, and this is what we’re here to watch.

You can hear them gathering, shrieking and whooping as we make our way to a ramp above a fence. A lively gang of young adults and juveniles await us, impatiently signalling for feeding to begin. The sanctuary staff toss in pieces of carrot, jackfruit and watermelon, and a curious riot ensues below — although hungry, the group observe a strict pecking order, which starts with the alpha male, a hairy black-faced bruiser. His name is Mowa (which means “A problem”). “Watch out for him,” chuckles Macanthony. “If he’s in a bad mood, he’ll throw stones, and his overarm spin wouldn’t disgrace the English team!”

Macanthony explains that none of the animals is allowed to breed — it’s because of the size of the island again. I ask: “How do you stop them?” To which Macanthony replies: “Contraceptive implants.” I feel a pang of sadness. These animals were mercifully rescued from cruelty, yet still can’t live natural lives; instead, they’ve become a sterile island community. As though reading my thoughts, Macanthony indicates a tiny infant who is playing nearby, turning somersaults, staring at us upside-down, bum in the air: “But, of course, as with all contraception, sometimes it doesn’t work. We’ve called her Surprise!”

The next day, we climb into a small, white- knuckle special and fly to Uganda’s southeastern corner, and Bwindi Gorilla Forest Camp. Here we have luxury tent accommodation, and sipping gin and tonics, we gaze at the view: in the foreground, flame trees with their vibrant orange blossoms, while further away the misty blue-green jungle of the mountain looks like a colossal waterfall. This area is known as the Impenetrable Forest. Are we really going to climb through it tomorrow? And are we going to find gorillas within?

“One party saw them within 15 minutes yesterday,” says Gadi, our trim, moustachioed guide from the Wildlife Authority, as he conducts the morning briefing. “Another took seven hours. If you don’t see them at all, you’ll get a refund. But if you have to turn back yourself — with, say, altitude sickness — there’s no refund.” I glance round our party of eight, filled with private fear: everyone else looks younger and fitter than me.

Gadi explains that we can hire porters. “Yes, please,” I say. Gadi gestures towards a crowd of young locals who are waiting eagerly on the road, and several run forward. Assigned to me is a girl with red-dyed hair and radiant smile, Tukakismirwa. Her name translates as “You can be happy”. I take this as a lucky omen. Also reassuring are two soldiers who’ll be coming along.

After a bone-rattling drive on dirt roads, we reach a point much further up the mountain. Gadi, who’s in radio contact with two trackers following a group of gorillas, leads us towards the nearest wall of foliage and cries: “Let’s penetrate the Impenetrable!”

I think he’s joking. He’s not. The interior is dark and dense, with tangled branches and lianas — Gadi hacks through these with a machete — and a spongy mush of leaves and moss underfoot. We follow in single file, the incline growing ever steeper. I’m quickly out of breath. Eventually, Gadi calls a rest stop. He communicates with his trackers, then says to us: “See how dry it is here — the rains never came this season — so the gorillas aren’t settling to eat, they keep climbing higher.” Noticing our collective dismay, he adds, “Now you understand why they’re called mountain gorillas.”

A few rest stops later, I’m in a bad way: gasping, sweating, my glasses fogged over.

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