4 star rating: Recommended 68 Reviews

Add your review

  • Address: Laguna Grande, Fajardo, Puerto Rico

San Juan ATTRACTIONS See all

Bioluminescent Bay Tours

By daylight, Fajardo’s bioluminescent lagoon appears just as scenic as any other bay on the tropical Puerto Rican coastline. But come nightfall, the Laguna Grande bio bay glows fluorescent with every movement and splash, thanks to the presence of microscopic plankton that thrive in the shallow Caribbean waters. Read on to learn how to take your own memorable Bio Bay tour.


The Basics

Bio bay tours allow visitors the chance to set the water aglow and create a trail of light with every stroke of a kayak paddle. To see the bioluminescence, night trips are offered around the cycles of the moon, with ideal timing on the darkest nights. These guided kayak tours are available departing from San Juan or Luquillo, which is set only nine miles (15 km) away. It’s common to couple kayaking with an afternoon nature walk to La Mina Falls in the nearby El Yunque National Forest.


What to Expect When Visiting the Bioluminescent Bay

Bio bay kayaking trips frequently set out in the early evening around sunset, launching from Las Croabas with a tour guide or instructor. These kayak tours travel through a dense collection of mangrove trees under a total canopy of darkness, and once you’re out of the mangrove tunnel, the stars above provide the only light by which to view the glowing waters, where the tips of your paddles will slowly begin to glow as they strike the liquid surface. There’s no swimming in the bay during this popular Puerto Rico vacation activity, but it’s easy to pass your hand through the water over the side of your kayak.


Why Does the Bio Bay Glow?

Although the glowing water often gives visitors a magical feeling, this spectacular natural wonder is actually caused by single-celled organisms called pyrodinium bahamense that are found in the Atlantic Ocean and glow when disturbed. The bay is surrounded by red mangrove trees, native to the surrounding El Yunque rainforest, that provide vitamin B12 to the marine plankton and create the perfect environment for their survival. There are only a handful of places in the world where this natural phenomenon is consistently found, two others of which are also on Puerto Rico, the Island of Enchantment: at Mosquito Bay on Vieques Island and the bay at La Parguera. 

How to Get There

Laguna Grande is located in the Las Cabezas de San Juan Nature Reserve just off the shores of Fajardo, about 40 miles (65 km) or an hour’s drive east of Old San Juan, a major tour departure point.

Tours & Tickets

See all

El Yunque Rain Forest Nature Walk and Bioluminescent Bay Kayaking Combo Tour, San Juan, null
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 3

El Yunque Rain Forest Nature Walk and Bioluminescent Bay Kayaking Combo Tour

5 star rating: Highly Recommended 129 Reviews

If you're looking for an active way to experience Puerto Rico's native environment, take this combo adventure from San Juan that includes a nature hike with a ...  Read more

Location: San Juan, Puerto Rico
Duration: 11 hours (approx.)

From USD $165.00
El Yunque Rainforest and Bio Bay All-Day Tour, San Juan, Day Trips
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 3

El Yunque Rainforest and Bio Bay All-Day Tour

4.5 star rating: Recommended 18 Reviews

Rainforest and Biobay combo tour experience two of Puerto Rico's most famous attractions in one tour during this full-day adventure. Visit the El Yunque ...  Read more

Location: San Juan, Puerto Rico
Duration: 10 hours 30 minutes (approx.)

From USD $150.00
Bioluminescent Bay Glass Bottom Kayak Tour from San Juan, San Juan, Day Trips
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

Bioluminescent Bay Glass Bottom Kayak Tour from San Juan

4 star rating: Recommended 56 Reviews

Join this fully-guided nighttime bioluminescent bay kayak adventure. Paddle your way through the mystical mangrove channels leading to Laguna Grande in a ...  Read more

Location: San Juan, Puerto Rico
Duration: 5 hours (approx.)

From USD $105.00
La Parguera Glowing Bioluminescent Bay Tour from San Juan, San Juan, Kayaking & Canoeing
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

La Parguera Glowing Bioluminescent Bay Tour from San Juan

5 star rating: Highly Recommended 6 Reviews

Experience one of Puerto Rico’s most magical bioluminescent bays on an 8-hour tour from San Juan. The bio bay at La Parguera is the island’s only ...  Read more

Location: San Juan, Puerto Rico
Duration: 8 hours (approx.)

From USD $159.20
Bioluminescent Bay Kayak Adventure Tour from San Juan, San Juan, Night Cruises
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

Bioluminescent Bay Kayak Adventure Tour from San Juan

4 star rating: Recommended 27 Reviews

This is one adventure not to be missed while in Puerto Rico! Join this fully-guided nighttime BioBay kayak adventure into one of the most amazing excursions of ...  Read more

Location: San Juan, Puerto Rico
Duration: 5 hours (approx.)

From USD $105.00
La Parguera Bio Bay Boat Tour from San Juan, San Juan, Kayaking & Canoeing
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

La Parguera Bio Bay Boat Tour from San Juan

4.5 star rating: Recommended 6 Reviews

Travel to La Parguera and see one of Puerto Rico's famous bioluminescent bays on this tour from San Juan. Experience one of the most unique natural ...  Read more

Location: San Juan, Puerto Rico
Duration: 9 hours (approx.)

From USD $175.00
Bioluminescent Kayak Adventure from San Juan, San Juan, Day Trips
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

Bioluminescent Kayak Adventure from San Juan

4 star rating: Recommended 140 Reviews

In Puerto Rico, your evening doesn't end when the sun goes down! Take part in an exciting kayak adventure on a bioluminescent bay not far from San Juan and be ...  Read more

Location: San Juan, Puerto Rico
Duration: 4 hours (approx.)

From USD $112.00
San Juan Bio Bay Kayak Adventure, San Juan, Kayaking & Canoeing
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

San Juan Bio Bay Kayak Adventure

4 star rating: Recommended 6 Reviews

Explore one of Puerto Rico's famous bioluminescent bays on this kayaking adventure from San Juan! Your guide will take you through the 'Big Lagoon', where you ...  Read more

Location: San Juan, Puerto Rico
Duration: 5 hours (approx.)

From USD $105.00

See all

Viator uses cookies to improve your experience on our website. Learn more about how we use cookies and how to change your cookie settings | Close message