This smaller island is a poor and scruffy fragment of East Africa. There is no night-life, the roads are terrible, and at one point I felt we were in real danger. But our three-night excursion there provided the most surprising and memorable part of our best-ever holiday.
Most British visitors to Zanzibar come for less than a week, staying only on the main island of Unguja. They arrive after a safari or a Kilimanjaro climb, flake out on a beach, and take a quick look around the extraordinary Zanzibar Town before heading for home. But the whole of Zanzibar, including Pemba, merits a longer stay.
My finest moment there came when the family floated over the drop-off from a coral reef, just a couple of snorkel strokes from the tiny beach on the islet of Misali. It made us gasp. We could see the hallucinogenic mountainside of coral falling steeply away to sandy depths 50 feet below. It looked awesomely, spookily deep to the two seven-year-olds. Way down at the bottom, a black fish the shape of an axehead and the size of one of the twins swam slowly into view.
Smaller fry with extreme colour schemes flicked around the big coral domes, brackets and shrubs. There were pink-and-grey sea cucumbers, giant clams two feet across with iridescent indigo and turquoise lips, and huge sea anemones. This was the most spectacular reef I had ever seen, and my children were marvelling at it, too. Could life ever get better?
The danger - perhaps imaginary, perhaps not - came during the six-mile boat trip back to Chake Chake, Pemba's modest capital. The journey out to Misali had been choppy once we cleared the mangrove swamp and the estuary and reached the open sea. The odd wave had splashed across our small, open fishing boat. This had no internal buoyancy, and the only safety devices were two old-fashioned red and white rings brought along just for us. The wind was stronger, the waves larger on the return leg. The wooden craft bucked, the outboard engine began to falter as the propeller lifted out of the water and our crew of three Pemban fishermen looked worried.
They ordered us sharply towards the stern, to keep it down in the water. Every fourth wave sent sheets of spray over the entire boat and we were completely soaked. As we picked our way carefully through swells higher than the gunwales, I became convinced that we would be swamped. No lifejackets, no distress flares, no lifeboats nor helicopters, and not much chance of making it to shore. What were we doing here? Then the approaching land began to shelter us, the waves died down and the crew began to chat. We seemed to have survived.
Pemba lies north of Unguja and getting there from the main island could not be easier. Every day, Mega Speed Liner's catamaran makes the crossing from Zanzibar Town to Mkoani at the southern end of the island in a little over two hours. We got around Pemba in a trusty Land Rover with one driver and one guide, Mr Kassim Ali Hamad of the state-owned and highly efficient Zanzibar Tourist Commission. We spent one day visiting Misali and the other at the island's northern tip, visiting the Ngezi Forest and Vumawimbi beach.
Ngezi is the only real remnant of rainforest left on either of Zanzibar's two islands. We were guided round a mile-long nature trail by a young, knowledgeable chief warden who seemed to be doing his best with very limited resources. We passed ponds and tall, liana-clad trees with gigantic buttress roots. There were frogs the size of a thumbnail, tiny snakes hurtling across the sandy path, and giant snails. Half-way round was a long-abandoned logging station. The machinery for sawing huge trunks into planks was rusting away, the concrete foundations crumbling beneath the invading trees. The conservation of this forest fragment receives no finance from any Western wildlife charity or government, and precious little from Zanzibar's own administration. I wanted there to be a wooden tower so that visitors could climb 50 feet into the canopy, and a stream of appreciative tourists and Pemban schoolchildren coming by. I wondered how long the forest would be able to survive.
Beyond Ngezi, past a rubber plantation, is Vumawimbi, a two-mile crescent of white, floury sand backed by whispering pine trees and coconut palms with a scattering of dugout canoes. There was not a single building. We swam across meadows of sea-grass to sandy islets exposed at low tide, and chased ghost crabs. It is said that construction of a luxury hotel will start there next year. Several such hotels, aimed at wealthy tourists rather than adventurous backpackers, are planned on Pemba, but so far only one small one has opened near Vumawimbi, built by a company that runs diving holidays.
Our Pemba nights were spent in Chake Chake's uncelestial Star Inn, opposite an enormous football stadium with four huge lighting towers but no lights. The Star is meant to be about the best of the simple, cheap guesthouses that Pemba offers. In the evenings before dinner - fried fish, fried squid or fried chicken - we strolled along the road. There were colossal spiders that hung their webs in the electricity cables and 10-inch-long, shiny centipedes with bodies as fat as a Smarties tube trundling on to the potholed asphalt.
Pemba's roads are flanked by big, shady mango trees and travelling on the better stretches was a delight. We rolled through a changing but ever green landscape of cassava gardens and plantations of clove trees. The roads are busy all day long with heavily laden bicycles, overcrowded little buses called dala dalas and carts pulled by small, sad-faced bullocks. Again and again we had to ask: "Why did the chicken cross the road?" Scrawny fowls, often with chicks in tow, always seemed to make their move in the wrong direction as we bore down on them. We passed clean over one small family, hearing frightened cheeps from beneath the car, but looking back we saw they had all survived.
The Schoon family - two adults, one 15-year-old and two seven-year-olds - paid pounds 5,400 for their 16-night holiday in Zanzibar, which was organised by Gane & Marshall International (0181-441 9592). This included economy- class flights from Heathrow to Zanzibar with Gulf Air, changing planes in Abu Dhabi on the way out and in Muscat on the return journey.
The total cost of the holiday came to almost pounds 7,000 once the costs of yellow-fever injections, anti-malaria tablets, Tanzanian tourist visas, essential Third World holiday equipment (such as a medical kit and water- purification tablets) and travel from home to Heathrow were added in. The Pemba portion of their package cost about pounds 600 including catamaran tickets, half-board accommodation, transfers from port to hotel, boat trip to Misali Island and a day-long visit to Ngezi Forest and beaches with a driver and guide plus two shorter excursions.
A tip: take your own snorkelling equipment. You cannot buy it in Zanzibar and you may not be able to hire it when you need to