
If you want to enjoy an amazing and eco-friendly attraction while traveling, head to Vieques, Puerto Rico. Vieques is home to Mosquito Bay, the brightest bioluminescent bay in the world.
Mosquito Bay is best known for its fascinating, glow-in-the-dark appearance. What makes it glow? Tiny, single-celled organisms known as dinoflagellates.
When dinoflagellates grow in large quantities and are stimulated by moving (such as paddling or splashing in the water), they light up and emit a stunning neon blue-green color. Everything they come in contact with takes on the same color, forming a beautiful reflection on the water.
Dinoflagellates rarely exist in high enough concentrations for people to notice. When they do, though, they create a stunning scene that people travel from all over the globe to see.
Only five ecosystems in the world have sufficient concentrations of dinoflagellates to achieve the title of bioluminescent bays. Three of them are found in Puerto Rico, including Mosquito Bay.
The quantity of dinoflagellates in Mosquito Bay ranges from approximately 1-2.1 million per gallon of water.
In 2006, this bay received the title of “Brightest Bioluminescent Bay in the World” by Guinness World Records. At the time, the bay contained roughly 700,000 dinoflagellates per gallon. However, the quantity decreased following Hurricane Maria in 2017.
Condé Nast Traveler also named Mosquito Bay “One of the Seven Wonders of the World” in 2020.

Mosquito Bay is one of the best to visit because of the lack of light pollution surrounding it. Visitors can also rent a kayak — some even have transparent bottoms — and paddle out onto the water to get a better view.
The best time to visit Mosquito Bay is during the new moon phase — when the sky is darkest. The bay is beautiful anytime, but it’s especially intriguing during the new moon, so plan your trip accordingly.