Skip to main content

Sheraton Caverns: Dive Kauai's Underwater Jungle of Lava

Check out this dramatic dive site off the coast of Kauai through the eyes of the local community.

By Katie Doyle | Updated On August 23, 2023
Share This Article :

Sheraton Caverns: Dive Kauai's Underwater Jungle of Lava

lava tube formations

The unique lava tube formations that make up Sheraton Caverns create eerie light patterns and awe-inspiring swim-throughs that play host to a wide variety of Hawaii marine life big and small.

Lucy Grigorian

When it comes to diving on Kauai, the fourth-largest island in the Hawaiian archipelago, it’s hard to beat the versatility of Sheraton Caverns, a dramatic undersea wonder on the south shore, where interesting topographic lava features, wildlife of all different species and sizes, and warm, calm waters abound. Marvin Otsuji, a local diver and owner of Seasport Divers, says the site serves as “a showcase where you can open the doors” to world-class diving on the Garden Island.

Sheraton Caverns is a signature dive site for Seasport because it celebrates just about everything divers could ask for. It’s conveniently located just 2 miles from Kukui'ula Harbor, parallel to the Sheraton Kauai Resort on the mainland and sandwiched between other iconic dive sites—Koloa Landing to the west, and Ice Box to the east. And it’s a site that appeals to divers of all ability levels (and even snorkelers). Best of all, Otsuji has learned he can expect a level of consistency at Sheraton Caverns that is found almost nowhere else on Kauai.

Related Reading: The Ultimate Guide to Scuba Diving Kauai

Born on the nearby island of Molokai, Otsuji has been living on Kauai since 1975. He started diving Sheraton Caverns in the early 1980s and marvels at how it has remained constant despite so much change back on land. “[Kauai] was kind of the best-kept secret for the longest time. I can remember when I first moved here, hotels couldn’t reach a 70 percent occupancy rate! Lately there’s new development— new businesses, new restaurants.”

Sheraton Caverns

Sheraton Caverns, Kauai

Lucy Grigorian

Best Kept Secret

Otsuji says Kauai is still a quiet and fulfilling place to live, where one can appreciate that “the lifestyle here is a lot simpler than most places.”The local dive community has built up a focus on preserving the oceans. Divers take full advantage of nearly year-round fantastic weather, but winter, when the water is at its most calm, is hands down the best time for diving at Sheraton Caverns. A two-tank dive plan presents plenty of time to explore the architectural contours and thread through the arches beneath the waves, where depths range from 20 to 65 feet. The light penetrating below the spacious chambers “gives you that eerie feeling,” Otsuji says.

“You basically get yourself settled at about 30 feet,” he explains, making it “a really easy dive for all levels. There’s octopuses, there’s frogfish, there’s whitetip sharks—all within a really small area.”

Related Reading: Where to Scuba Dive in Hawaii

Lucy Grigorian, social media manager at Seasport Divers, also marvels at all the life concentrated around the formations. “Sheraton Caverns is one of my personal favorite dive sites around Kauai,” says Grigorian, adding that the site is enjoyable both in the morning and at night.

colorful fish swirl around the lava tube formations

Captivating swim-throughs and charismatic sea turtles make this site off Kauai a popular dive location.

Lucy Grigorian

Turtles for Days

Another reason everyone loves it: “Turtles for days.”

Hawaiian green sea turtles are the stars of the show. Otsuji says anywhere from 25 to 200 turtles came ashore every night during the past year to rest in Poipu. They feast on the abundant algae in the waters around Sheraton Caverns, and their abundance is a source of local pride on Kauai. Monk seals occasionally swing by, and a lucky few might catch a glimpse of manta rays and humpback whales. In addition to the larger marine life, schools of colorful fish swirl around the lava tube formations. Macro photography enthusiasts can investigate crevices where smaller creatures might be hiding in camouflage.

Otsuji is partial to the warm water off this part of Kauai’s coastline, which means he can don a typical shorty and be comfortable most of the time. He notes that it’s a good idea to pack additional layers, such as a hooded vest, just in case. Divers heading out to the caverns typically spend half a day exploring, beginning either first thing in the morning or around noon. Those taking a morning shift can start the day with a cup of fresh local coffee, and there’s always an abundance of fresh poke waiting when you stop to refuel at the end of a day in paradise.

coffee illustration

A sip of Kauai’s famous coffee is a must for any diver looking to fuel up for a dive at Sheraton Caverns.

Cassidy Vincent

Site Spotlight

A sip of Kauai’s famous coffee is a must for any diver looking to fuel up for a dive at Sheraton Caverns.

Coffee farming has been a part of the island for nearly 200 years. Kauai was home to the state’s fi rst commercial coffee endeavor, which began in Koloa in 1836. Over the years, sugar cane and other crops supplanted coffee in Hawaii, but the beans made a comeback in the 1980s.

The local coffee pours Otsuji recommends come from Little Fish Coffee on Poipu Road, which he says has “always got a big line but it’s open pretty early.” If you’re traveling from the west for a morning dive, swing by Kalaheo Café & Coffee Co. or Dark Horse Coffee Roasters in Koloa.

Need To Know


Expect to see 100-plus feet of visibility on a good day, with 40 to 50 feet being the lower end of the spectrum, Otsuji says. Water temps range from the high 70s to low 80s. “Cold” water means temps dip down to about 72 degrees. “It’s pretty calm,” Otsuji explains, cautioning that “in the summertime when the waves come up, sometimes it gets a little bit tough.”

When to Visit

Dive Sheraton Caverns in winter to take advantage of the best weather.

How to Dive It

The caverns lie just offshore from the town of Poipu, easily accessible via a formal dive tour or private boat.

What to Wear

5 mm wetsuit in winter; 3 mm in summer.

Local PADI Dive Shop

Seasport Divers Koloa, Hawaii