BOMBOM, Sao Tome and Principe - Flying into the tiny island of Principe off Africa's west coast brings a sense of traveling back in time.

Seen from over the Atlantic, the dense tropical jungle coats the volcanic terrain down to a turquoise sea and golden beaches reachable only by boat. It looks like a prehistoric land that time forgot.

Principe is one of the poorest spots on earth in dollar terms. But in terms of virgin tropical landscapes it is one of the wealthiest, according to Rombout Swanborn, a Dutch businessman and conservationist.

Swanborn recently purchased two hotels on Principe and, backed by local authorities, aims to plug this island of about 6,000 people into the ecotourism boom now spreading across West Africa.

Ecotourism took off in eastern Africa in the early 1990s. Underdeveloped countries such as Uganda, Tanzania and Kenya discovered they had what vacationers from developed countries sought - raw wilderness rich in animal life.

Now the business is gaining traction in the western part of the African continent, too.

Ecotourism is flourishing in Gabon and Ghana. Angola and Nigeria are also signing up. Sao Tome and Principe, a twin-island nation in the Gulf of Guinea, aims to become the latest.

"The people here are sitting on a pot of gold," said Swanborn, who also operates four ecotourism developments in Gabon.

The Madrid, Spain-based World Tourism Organization in October described Africa as the industry's "star performer." Growth in visitors is predicted to be around 10 percent this year, more than double the world average.

"One can safely say that the growth we observe in Africa . . . is mainly based on ecotourism growth," said Eugenio Yuris, head of the WTO's sustainable tourism section.

The United Nations and international conservation bodies such as the World Wildlife Fund are backing the ecotourism trend. They view the development of sustainable tourism as a way of wedding local needs and care for the environment.

There are potential pitfalls, though.

Neel Inamdar, a senior adviser at Washington, D.C.-based Conservation International, a nonprofit organization, points out that Kenya has fought hard to recover from the damage wrought by high-volume, low-cost ecotourism.

"You need a strong regulatory environment, with bodies that will stand up to the industry," Inamdar said.

Principe island, just north of the equator, fits the bill of a tropical paradise.

Just a few hundred people live in its seaside capital, Santo Antonio. The rest are scattered across small communities of clapboard houses and tumbledown former plantation buildings where they scrape a living from farming and fishing. The jungle spills down to beaches where you can spend an entire day and the only footprints in the sand are your own.

The Atlantic rainforest is sprinkled with colorful birds, and waterfalls. In certain seasons, sea turtles lay eggs on the beaches and whales come within view of land.

This country is not all that it could be as a vacation destination. There are few international-standard hotels. But tourism development is gathering pace. Portugal's Pestana Group, which runs a resort on Sao Tome island, is building a development in the capital, also called Sao Tome, that includes a five-star hotel, a casino and villas.

Arlecio Costa, local director of the Falcon Group, is developing a huge project on the northern tip of Sao Tome island called Lago Azul (Blue Lagoon) with South African investors. The $380 million development, scheduled to open in five years, includes a quay for cruise liners, an 18-hole golf course, a conference center and a hotel with a health spa. The project will leave a large footprint, but Costa insists its biggest selling point is the area's natural beauty, especially the nearby Obo National Park.

Sao Tome and Principe was a largely overlooked country until it found major oil reserves, estimated at 11 billion barrels, in its offshore waters a few years ago. That discovery brought foreign governments and international oil companies.

Costa reckons tourism is the way forward. "The oil will run out one day," he said. "Tourism can be forever, if you take care of it." *