The Island of Hawaii is bigger than big; it’s absolutely huge. As the largest and southeasternmost of the chain, it’s the largest in the United States, comprises 63 percent of the state’s land, but is only home to 13 percent of its people. With more than 4,000 square miles — that’s 80 times larger than San Francisco — it boasts more than 313 miles of shoreline for its 100 beaches featuring black, green, and white sand. It also has two main cities (Kailua-Kona and Hilo, each with its own international airport), two active volcanoes (Kilauea and Mauna Loa in the southeast), and some of the world’s best coffee.
The Kohala Coast on the northwest side and the Kailua-Kona south of it are both equally popular for water sports because they offer dry and typically sunny weather, though you may often get drenched by a quick-moving afternoon storm. There are more than 100 dive sites around the Big Island with an amazing variety of sea life. Visibility averages around 60 to 100 feet.
What You Can See: Hawaiian Green Sea Turtles are more plentiful on the other islands, but can be seen on dives along the Hilo coast — please remember not to touch them or hassle them in any way. Around this island, you can see schools of large manta rays, inch-long nudibranchs, spinner dolphins and volcanic lava tubes. Octopi, eagle rays, moray eels, swarms of colorful fish including the “Humuhumu” state fish, and a wide variety of sharks are also common sightings. About 20 percent of the fish you’ll see are endemic to Hawaii. Humpback Whales can often be seen on dive trips near Hilo’s break wall during their migration season from late fall to early spring.
Water Temperatures: The average water temperature around the Island of Hawaii is similar to the other islands — ranging between 76 degrees to 82 degrees Fahrenheit year-round — and warmest between May to December. Whether swimming, snorkeling, or rolling off a boat to dive, the water always feels cool because it’s 10 to 20 degrees below your body temperature. Wearing a shorty 3-5mm wetsuit, hoodie, and gloves will help prevent heat loss while underwater, with an extra layer of a thin dive skin beneath.
Here are the best places to scuba dive in the Big Island of Hawaii.
Feature photo: Sarah Humer
3-Room Cave, Kona Coast
South of Kona off Captain Cook beach, this dive available during calm seas is literally what its name implies: a 200-foot wide lava tube with three big rooms. Dive operators provide a rope line in and out and cyalume light sticks so every diver can be identified, but bring a flashlight, too. You may see lobsters, shrimp, puffer fish, nudibranchs, moray eels, and more among the lava and corals. diverprofile.com
Black Coral Forest, South Coast
Black coral is a living memory of these volcanic islands — and the Island of Hawaii is still active. Your boat will anchor over a sand chute and 90 feet down, you’ll see the first of a forest of black coral trees, as well as scary-looking but harmless barracuda, viper eels, and all types of reef fish. hawaiiscubadiving.com
Blackwater Dive, Kona Coast
For something different, you may want to do this boat dive in pitch dark water that’s 3,000-feet deep along the continental shelf into the abyss. I’ve not done this but divers rave about a serene experience to see a variety of animals at night as you float about 50 feet below your boat on a tether. You must have logged at least 25 dives to quality and had several night dives under your weight belt. You may see all kinds of bigger fish and pelagics, bioluminescent fish, colorful coral, and more. bigislanddivers.com
Kona Aggressor II Liveaboard Boat
This well-known vessel out of the Kailua-Kona area can accommodate up to 14 passengers. It offers the opportunity to take up to 5 dives per day at a wide variety of sites and up to 27 dives on a 7-day charter versus a typical 1-day, 2- or 3-tank charter boat. That’s a ton of bottom time and the best bang for your underwater buck. Most of their sites are among the 22 it offers along the western coast of the Island of Hawaii, as far away as South Point in the southeast. aggressor.com
“Manta Heaven” Boat Dive, Kona Coast
Another option is a sunset boat dive or daytime dive out of Kona. After motoring north eight miles to “Manta Heaven,” your operator enables you to spend time with even more large rays (“Big Bertha” has a wingspan of 16 feet) who weigh about 1,000 lbs. each. The average number of rays seen here is about 10. The rays’ presence is not guaranteed, but if you don’t see some, the operators will give you a free rain check. mantarayadvocates.com
“Manta Village” Night Dive, Kona Coast
“Manta Village” is seven miles south of Kona, off the coast of the Sheraton Keauhou Bay Resort & Spa. It’s the original and most popular place to see these harmless, but fascinating mantas — aka “devil fish.” Shore lights attracting marine plankton after sunset attract rays who are comfortable swimming around snorkelers and divers at 20- to 30-foot depths. The average number of rays seen per day is about four. mantarayadvocates.com
Sea Turtle Cove, Hilo
Off the island’s east coast, the open water is more prone to stronger winds and currents. Departing from Wailoa Boat Harbor, dive boats journey out to sheltered coves where you can see schools of large Hawaii Green Sea Turtles, as well as manta and eagle rays, moray eels, octopi, tropical reef fish, and colorful corals. hilooceanadventures.com
Shark Dive, Kona Coast
If diving in the dark doesn’t raise your eyebrows, how about an adventure three miles off the coast to witness one of the world’s best places to encounter many large shark species? This operator has been offering these dive trips to watch hammerheads, tiger, oceanic white tip, Galapagos, sandbar, mako, reef and black tip, even great white sharks — which are rarely spotted — 250 days a year, over 15 years. That means there’s a high probability that both experienced and novice divers can have a once-in-a-lifetime dive or two, as well as seeing humpbacks, pilot, sperm whales, dolphins, tuna, ocean sunfish, and more. The operator claims that if you don’t see some, you’ll get your $250 back. Seeing them up-close underwater is an adrenaline rush that you’ll remember for years, but if you don’t want to get wet, you can also just watch from the boat. konasharkdiving.com