I am sitting in a tiny airport in Puerto Rico, called Ceiba, awaiting what is to be the shortest flight of my life. The gate agents have recorded all of our weight — from checked luggage to carry-on bags and even our persons — for the small charter plane that will take us over to Vieques Island.

The door to the tarmac opens and a woman sticks her head in, beginning to call out by last name the short list of passengers for our flight. Guess that’s our boarding call.

Flying to the island of Vieques from mainland Puerto Rico (of course, itself an island) doesn’t take very long; in fact, blink and you just about miss it. The props start turning, we lift off the runway strip and barely have enough time to get up in the air before we are starting the descent. When I’m back on the ground on Vieques Island, seven minutes have passed since taking off.

La Isla de Vieques is like nowhere else in the Caribbean. Most of its land remains undeveloped; it was here that the U.S. Navy used, and abused, 60 percent of the island for sixty years as a training site. In 2003 the Navy left Vieques and passed control back to the Department of the Interior — who had to remove explosives and military waste to the tune of more than $200 million. The Navy’s occupation of Vieques was controversial at best; in 1999 Puerto Rico Governor Pedro Rosello said, “Never again shall we tolerate abuse of a magnitude and scope the likes of which no community in any of the fifty states would ever be asked to tolerate.”

That was then; this is now. Today the Navy land is under Fish and Wildlife Administration, making the island the largest national refuge in the Caribbean. Wild horses roam around freely; the beaches are pristine and undeveloped, surrounded by native flora instead of concrete. There are no McDonald’s, no kitschy souvenir stands.

Vieques was voted the best Caribbean island by Travel + Leisure, and made Conde Nast Traveler’s 2011 Hot List.

And Vieques Island is home to the reason we have come: the brightest bioluminescent bay in the world. The bio-bay creates a sea that glows in the dark; there are five such places in the world and three of them are in Puerto Rico. The largest, and most filled with bioluminescence, is Mosquito Bay here on Vieques. A microscopic organism from the dinoflagellata family lives in these waters, and bioluminescence is its natural defense system.

When the tiny creatures are disturbed, they give off a chemical reaction that produces light. This attracts bigger water predators, who feed on the creatures who were planning on eating the dinoflagella. And for those of us witnessing this phenomenon, it creates a magical, light-filled show that looks like blue fireworks underwater.

We go out on Mosquito Bay after sunset with Island Adventures, a highly-recommended operator of excursions to the bay. After a bus ride down the bumpiest dirt road imaginable, trees scraping along the sides and top of the bus with every lurch, we arrive at the water’s edge to board an electric pontoon boat. This boat will take us silently through the water to witness the bio-luminescent marvel at work.

As the boat moves through the bay, fish dart away from it. As they swim and even jump through the water, they leave a wake of brightly glowing contrails behind. It really is quite spectacular. We are allowed to put our feet in the water and the splashing creates more glowing droplets. The Island Adventure biologist guides pull buckets of the H2O up onto the boat for us to examine and play with, but people are not allowed to get into the water. Sunscreen, perfumes, shampoo, deodorant and other things we use are very dangerous to the bay and our little dinoflagellate friends.

I learn that, although the microscopic creatures are present in all the ocean and sea water of the world, typically they are at a volume of 30-50 per gallon of water. Here in Mosquito Bay, there are more than 700,000 of them per gallon, creating this rare and endangered natural wonder.

I recommend that you don’t come to Puerto Rico without visiting this magical place yourself. Contact Island Adventures for a tour, and stay in style at the new W Retreat & Spa. The W has a comfortable island sanctuary vibe, with the luxury and exquisite food that you’ve come to expect from W — and some of the most spectacular sunsets it’s possible to witness in the Caribbean.

To get to Vieques, take the Vieques Air Link; there is also a ferry for around $4, though it sometimes runs erratically.

If the glowing waters don’t give you enough outdoors and wildlife adventure, there is plenty more to be had in Puerto Rico. Of course there are all the popular water activities from snorkeling and diving to kite-surfing, kayaking and parasailing. What you might not know — I certainly didn’t — is that Puerto Rico is home to the largest rainforest in United States territory.

El Yunque National Rain Forest is 29,000 acres of incredible biodiversity; in fact, in these few acres there is more biodiversity than in the millions of acres of all the other U.S. National Parks and Forests combined.

“This is a very special place,” says Pablo Cruz, Forest Supervisor. He begins telling me about the ecological importance and history of the rain forest, but then he pauses. “I’m not a hippie,” he starts, feeling the need to make that disclaimer first. He goes on to reveal the sad history of the land.

When the Spanish made their conquest of Puerto Rico 400 years ago, they deforested the entire island. They created agricultural land out of everything, planting their endless tobacco and sugar cane crops.

“Most all of the forest and vegetation on Puerto Rico is less than 400 years old,” Cruz says. “The only old-growth to survive is here in the oldest parts of El Yunque, which were on too steep of inclines for farming.”

The native people didn’t settle in the area that is now El Yunque, instead using the cloud forest as a holy place for ceremonies and religious rites. The name El Yunque, in fact, is an indigenous word that means in the heavens. The U.S. forest system had to learn about rain forests here in El Yunque, as all previous forestry had come from Germany and was all about temperate forests. This national preserve is the premiere learning spot for rain forest science and preservation in the entire world.

Although I only have the morning, I could easily spend an entire day hiking around El Yunque. Excellently groomed, marked trails run through the entire forest, ranging in difficulty from an easy stroll close to the visitor center, manageable by nearly anyone, to slightly longer and more strenuous hikes. There are a number of unique plant and animal species, such as the endangered Puerto Rican Parrot and the tiny coqui tree frogs that you will hear serenading each evening on the island. There are 150 species of fern and 240 tree species — 88 of which are rare and 23 found only in El Yunque.

Guided forest tours are available, and camping (free with permit) and lodging are also offered. There is a beautiful waterfall and interesting tower that gives terrific aerial views of the rain forest and surrounding parts of Puerto Rico.

---

To visit or stay at the rain forest, check out the El Yunque National Rain Forest website.