Ishigaki Island is a Coral Paradise! A Guide to Enjoying and Exploring Its Coral Reefs

Ishigaki Island, part of the Yaeyama Islands, is one of Japan’s most nature-rich remote islands. While the white sand beaches and crystal-clear blue sea are undoubtedly stunning, what we’d really like to highlight are the vibrant coral reefs that surround the island. Together with the rest of the Yaeyama Islands, Ishigaki is known for its abundance of beautiful coral reefs.

In this guide, we’ll introduce how to appreciate the world of coral in Ishigaki—from understanding coral ecology to how best to enjoy it and where to observe it. Discover the beauty of coral and make the most of your time in this tropical paradise!

1. What Kind of Creature Is Coral?

Coral often looks like branching plants or sometimes even rough rocks. Unlike fish or other marine animals, it doesn’t move at all. However, coral belongs to the same group of organisms as sea anemones and jellyfish, known as cnidarians.

What we commonly envision as a coral reef is actually a colony made up of individual polyps sharing a common skeleton. There are many types of coral—over 600 species have been identified worldwide, and more than 400 in Japan alone. Okinawa is home to around 90% of the coral species found in Japan.

Among Okinawa’s coral-rich areas, Ishigaki Island stands out as the region with the greatest variety of coral species in Japan, making it an internationally valuable location. The coastline of the Shiraho district in eastern Ishigaki is especially famous, boasting the Shiraho Coral Reef, which stretches about 10 km southeast from the shore with a maximum width of 1 km. It’s also known as the site of the largest blue coral colony in the Northern Hemisphere.

2. Ishigaki Island’s Representative Corals: Blue Coral and Hama Coral

Blue coral only inhabits limited sea areas even within the Shiraho district. Although the name might suggest a blue appearance, blue coral colonies are actually brownish and leaf-shaped. Some grow to form clusters as tall as one meter.

Why is it called blue coral? The secret lies in its skeleton. Most corals have white skeletons made of calcium carbonate, but blue coral has a blue skeleton. This is because it contains a high concentration of iron, giving it its distinctive color and name.

Another iconic coral of Ishigaki is the Hama coral. A well-known variety found in Shiraho is the yellowish Yubieda Hama coral, which features distinctively branched polyps. Ishigaki is one of the few places where large colonies of this coral can be seen. The tropical fish swimming among these golden coral fields create a view so stunning it resembles a vibrant underwater flower garden.

3. Learn About Ishigaki’s Coral at “Shiraho Coral Village”

Shiraho Coral Village is a facility established in 2000 to help preserve the Shiraho coral reef. It was built thanks to donations and community support, aiming to protect coral reefs whose numbers have been steadily declining.

The facility works in collaboration with local Shiraho residents, focusing on coral reef research and environmental conservation. Inside, you can learn about coral ecology, its relationship with nature, and facts about Shiraho’s ocean through various exhibits.

The village also has tables and chairs for resting. On Sundays, the courtyard hosts a local market offering Ishigaki’s fresh vegetables and fruits, as well as handmade accessories—highly recommended for visitors. Occasional live performances of Yaeyama folk songs and other local events are also featured.

4. Take a Leisurely Underwater Walk Observing Coral Through Diving

If you want to observe coral reefs up close, diving is highly recommended! Diving allows you to go deeper underwater, where you can encounter hundreds of coral species that aren’t visible in the shallows.

The northern part of Ishigaki Island is especially known for its crystal-clear waters, making it the perfect location to gaze upon coral reefs that stretch as far as the eye can see beneath the transparent sea. Additionally, you’ll find plenty of vibrant tropical fish living near the reefs, making the scenery truly enchanting and mesmerizing.

One of the highlights of diving here is the chance to swim with friendly manta rays. While many people think diving requires a license, most local diving shops offer beginner-friendly “trial diving” tours. If you’re considering a diving experience, we recommend Ishigaki Blue Dive. And if you’d like to pursue a license, they also offer certification courses.

5. "Sokochi Offshore Paradise": A Diving Spot with Coral and Sea Turtles

Sokochi Offshore, located near the scenic Kabira Bay, is known for its exceptionally clear and beautiful waters. The diving spot called Sokochi Offshore Paradise, with depths ranging from 5m to 25m, is ranked among the top three coral viewing locations in Ishigaki.

It features a landscape of coral-covered formations that resemble a vast flower field beneath the sea, teeming with schools of fish. Truly, it lives up to its name—a paradise. The area also boasts a high chance of encountering sea turtles, and if you’re lucky, you might even spot rare creatures like spotted eagle rays or Napoleon fish.

It’s a perfect spot for meeting adorable sea creatures alongside stunning coral reefs. The currents are minimal, making it a safe and enjoyable experience for beginners. For diving at Sokochi Offshore Paradise, we recommend the “Pushiinu Shima Ishigaki Shop” which offers half-day and full-day trial diving experiences.

6. Glass-Bottom Boats for All Ages — Enjoy Coral Without Getting Wet

If you're interested in seeing coral reefs but prefer not to get wet, glass-bottom boat tours are a great option! These boats have transparent glass floors, allowing you to view the beautiful, clear underwater world from above.

Since there’s no need to dive in, it’s perfect for families with small children, seniors, or anyone who prefers to stay dry. It's an excellent activity for couples, too. For the best glass-bottom boat experience, head to the Sekisei Lagoon near Taketomi Island, where vibrant coral reefs flourish.

Sekisei Lagoon, located between Ishigaki and Iriomote Islands, is one of Japan’s largest coral reef areas. Through the boat’s glass panel, you can view a diverse range of corals—from table corals to branching varieties—each with different shapes and colors. Glass-bottom boat tours are operated by Nansei Kanko Co., Ltd., located inside the Ishigaki Port Terminal.

7. Snorkeling in Shallow Waters for Those Who Aren’t Comfortable with Diving

If full-scale diving feels intimidating but you still want to casually enter the water and see coral reefs, then snorkeling is highly recommended! Snorkeling is a marine activity where you swim in shallow water using a snorkel.

Because it takes place in shallower waters than diving, even beginners or those who aren’t confident swimmers can participate with peace of mind. In Ishigaki Island, Osaki Hanagoi Reef and Uganzaki Bonbon Square are ideal snorkeling spots thanks to their calm currents. These two locations are also home to the iconic blue coral species.

Another top recommendation is Sekisei Lagoon, the largest coral reef area in Japan. You can experience snorkeling here with the help of the specialized shop Shimeragi (皇). Their course called “Landing on the Phantom Island & Coral Garden Snorkeling” includes a visit to Hamajima, a sandbar that appears with the tides, as well as snorkeling in expansive coral reef areas.

8. For One of Ishigaki’s Finest Coral Reefs, Visit Shiraho Beach

Shiraho Beach lies within the Ishigaki Island National Park. In the Shiraho area, over 120 types of coral inhabit the waters, including large clusters of blue coral and stony coral. If you're planning to snorkel at Shiraho Beach, we recommend joining a tour with Blue Coral.

This shop is conveniently located about 9 minutes by car from Ishigaki Airport. Their snorkeling tours use private boats equipped with restrooms and guide you to calm, safe areas where you can see coral reefs and tropical fish like clownfish.

They also provide free drinks, which is a nice bonus! The shop is equipped with showers and changing rooms, so you can enjoy your snorkeling trip worry-free. For beginners, they offer snorkeling lectures and rental equipment plans, making it easy to join even if all you bring is your swimsuit.

◎ Summary

Ishigaki Island is home to many coral reefs—some of the richest in Okinawa Prefecture. Coral is a very delicate organism, and various conservation efforts are underway across Okinawa. There are many ways to learn about coral ecosystems and support preservation, whether through educational facilities, diving, snorkeling, or observing reefs via glass-bottom boats.

While Ishigaki has many excellent coral observation spots, some beaches lack supervision. That’s why joining a tour is the safest and most recommended option for diving and snorkeling. Always wear proper gear to prevent injury or drifting in the ocean.

If you're interested in exploring the coral reefs of Ishigaki Island, use this guide to choose the method that suits you best and enjoy the vibrant beauty of these underwater wonders.