The streets are sand. Boys play baseball with driftwood for bats. The only two vehicles are a garbage truck and a water truck.

Life is slow and simple on Los Roques archipelago, but as the world discovers what has been one of the best-kept secrets of the Caribbean, the pace may be picking up.Thousands of tourists from Canada, Germany, Italy, the United States and other countries are arriving, captivated by the pristine chain of 42 islands surrounded by coral reefs and 300 other tiny islets and sand cays.

"It doesn't look real," marveled my sister Allison during my family's recent trip.

The sea is shades of turquoise, aqua and emerald. The white sand is powder soft.

With a snorkeling mask, the underwater world came alive in spectacular fashion.

Black angel fish with yellow stripes, rainbow-colored parrot fish and yellowtail snappers swarmed in the crystalline water. Propelled by flippers and arms at your side, you get the sensation that you've become part of the sea yourself.

At one point, though, our ecstasy was abruptly interrupted when we met a 5-foot barracuda. The razor-toothed beast brushed by our tour guide and sent us swimming for shore.

Los Roques (The Rocks), 95 miles off Venezuela's coast, boasts 280 species of exotic fish such as puffy porcupine fish, royal blue angelfish, moray eels, sting rays, manta rays and black-tip sharks.

It also has all 87 species of coral found in the Caribbean Sea, including gonia, brain and fire. The skies are filled with 92 species of birds: frigates, brown boobies, scarlet ibises.

Most of Los Roques remains unspoiled, thanks to its remoteness and the fact the desalination plant that provides fresh water on El Gran Roque, the only permanent settlement, was barely pumping until a recent overhaul.

A few years ago, only a few of the 240 dwellings served as family-run guest houses, called "posadas." Today, there are 50. On nearby Madrizqui Island, Venezuela's richest families own a dozen vacation houses.

While tourism officials are happy more visitors are flocking to the islands (58,000 last year), environmentalists warn an onslaught could be disastrous.

Coral reefs are the so-called rain forests of the sea because of the high number of species they harbor and help breed. Yet, merely touching a reef can kill that spot by destroying a vital filmy plant that covers the surface and gives off the coral's distinctive bright colors.

"In very little time you can destroy a colony that took a thousand years to develop," says parks service head Miguel Matany. Tourists have killed many of the world's most heavily visited coral reefs.

Venezuela wants to avoid that fate. In 1972 it declared Los Roques a national park, making the 50,000-acre zone one of the Caribbean's largest marine preserves. The decree prohibited new building and limited the number of islands tourists can visit.

Officials say the high cost of traveling to Los Roques should help keep down the number of visitors. The government also plans to create environmental education programs and more than triple the number of park guards to 35.

Environmentalists worry that Venezuela's notoriously disorganized government won't follow through.

Most tourists get to Los Roques by taking a half-hour flight from Caracas or popular Margarita Island. There is no airport; just an airstrip and a check-in booth.

Fishermen will take you out to the other islands on their colorful wooden boats, which they beach on El Gran Roque near hungry pelicans dive-bombing for fish in the shallows. Or you can sail aboard one of the 55-foot catamarans run by tour companies.

Visitors often cap off the day by taking a sunset hike up a hill on El Gran Roque to an old lighthouse the Dutch built of coral, conch shells and stones. Once there, they relish the breathtaking view of the islands and anchored sailboats.

From that vantage point it's easy to see why Christopher Columbus, stopping off at Los Roques five centuries ago, declared them "Heaven on Earth."