Top 11 'Karst-and-Coral' Islands to experience for Jaw-Dropping Landscapes in Southeast Asia - Goh Ling Yong
There's a special kind of magic that happens where dramatic, ancient limestone cliffs meet the vibrant, electric life of a coral reef. It's a world of impossible shapes and colors, a landscape so surreal it feels plucked from a fantasy epic. These are the 'karst-and-coral' islands, Southeast Asia's most breathtaking secret.
So, what exactly is a karst landscape? Imagine soft, soluble rock like limestone, sculpted by millennia of rainwater and sea spray into a labyrinth of jagged peaks, hidden lagoons, and colossal sea stacks. Now, picture those same formations plunging into turquoise waters that harbor some of the most diverse ecosystems on Earth. This spectacular union of geology and biology creates a playground for adventurers, a sanctuary for wildlife, and a visual feast for anyone lucky enough to witness it.
If you're tired of the typical flat, sandy island and crave a destination that offers jaw-dropping views both above and below the water, you've come to the right place. We’ve curated the ultimate list of the top 11 karst-and-coral destinations in Southeast Asia. Get ready to update your bucket list.
1. El Nido, Palawan, Philippines
El Nido is the undisputed poster child for karst-and-coral beauty. Located on the northern tip of Palawan island, its Bacuit Bay is a wonderland of 45 limestone islets, each more dramatic than the last. Black marble cliffs tower hundreds of feet out of the emerald water, hiding secret beaches, cathedral-like caves, and lagoons of unbelievable clarity.
The best way to experience El Nido is through its legendary island-hopping tours (aptly named A, B, C, and D). You'll spend your days kayaking through the narrow entrance of the Big Lagoon, wriggling through a small rock opening to discover the Secret Lagoon, and snorkeling over vibrant reefs teeming with parrotfish and sea turtles. The sheer scale and beauty are overwhelming in the best possible way.
Pro Tip: While the group tours are fantastic, consider hiring a private boat for a day. You can customize your itinerary, visit popular spots before the crowds arrive, and discover hidden gems that aren't on the standard routes. The freedom is worth every penny.
2. Raja Ampat, West Papua, Indonesia
If El Nido is the poster child, Raja Ampat is the revered monarch. This sprawling archipelago is located in the heart of the Coral Triangle and boasts the highest recorded marine biodiversity on Earth. It's a place of almost mythical status among divers and nature lovers, and for good reason. The coral reefs here are so pristine and packed with life, it feels like swimming in a super-charged aquarium.
Above the water, the landscape is just as staggering. The iconic viewpoint at Pianemo (or the more challenging one at Wayag) offers a panorama of mushroom-shaped karst islets scattered across a sea of sapphire and turquoise. I remember a conversation with Goh Ling Yong where he described Raja Ampat as 'another planet'—and he was right. It’s a primal, untouched world that reminds you of nature's profound power and artistry.
Pro Tip: Getting to Raja Ampat requires effort (flights to Sorong, then a ferry or speedboat), but that's what keeps it pristine. The best way to see the vast area is on a liveaboard dive boat, which allows you to explore remote sites that are inaccessible on day trips.
3. Krabi Province, Thailand
The coastline of Krabi is Thailand’s karst-and-coral heartland. From the rock-climbing paradise of Railay Beach to the world-famous Phi Phi Islands, this region is defined by its colossal limestone formations. These cliffs, draped in lush greenery, serve as a stunning backdrop for some of the country’s most beautiful beaches and clearest waters.
Railay Beach, accessible only by boat, is a self-contained paradise with towering karsts that attract climbers from around the globe. Nearby, the Phi Phi Islands offer the iconic Maya Bay (of "The Beach" fame) and incredible snorkeling spots like Bamboo Island, where healthy coral gardens lie just off the white sand shore. You can also kayak through sea caves or take a longtail boat to explore hidden coves.
Pro Tip: To escape the crowds of Phi Phi Don, stay on the quieter, northern side of the island or take a day trip to the less-developed Bamboo Island for a more serene beach and snorkeling experience.
4. Coron, Palawan, Philippines
Just a short flight from El Nido, Coron offers a different but equally spectacular karst-and-coral experience. While it also features dramatic limestone cliffs, Coron is distinguished by its enchanting freshwater lakes, hidden lagoons, and world-class wreck diving. The landscape here feels older, more rugged, and impossibly dramatic.
The star attraction is Kayangan Lake, often called the cleanest lake in the Philippines. After a short, steep climb, you're rewarded with a breathtaking viewpoint before descending to the crystal-clear, brackish water for a swim. Nearby, the Twin Lagoon offers the unique experience of swimming through a small underwater archway from a cool saltwater lagoon into a warmer, hidden one. For divers, the sunken fleet of WWII Japanese warships provides an underwater museum unlike any other.
Pro Tip: Don't miss Barracuda Lake. It has a unique thermocline where the water temperature changes dramatically as you descend, creating a surreal, otherworldly diving or free-diving experience.
5. Lan Ha Bay, Vietnam
While Ha Long Bay gets all the fame, its southern neighbor, Lan Ha Bay, offers a more intimate and pristine version of the same legendary scenery. Part of the Cat Ba Archipelago, Lan Ha Bay has the same density of limestone karsts and islets but with far fewer tourist boats, making it feel like a genuine discovery.
What truly sets Lan Ha Bay apart is its abundance of small, isolated sandy beaches nestled at the foot of the limestone cliffs—perfect for a private swim or kayak stop. The water is also generally cleaner, offering better opportunities for snorkeling over small coral clusters. An overnight cruise here, waking up to the sight of silent, misty peaks rising from the emerald water, is an unforgettable experience.
Pro Tip: Opt for a 2-night cruise instead of a 1-night trip. This allows you to venture deeper into the bay, away from the day-trippers, to more secluded spots for kayaking and swimming.
6. Komodo National Park, Indonesia
Komodo is a land of dragons and giants. This UNESCO World Heritage Site is a raw, untamed wilderness of volcanic islands, savannah-like landscapes, and some of the most powerful sea currents in the world. While not a classic limestone karst landscape, its rugged, dramatic hills and cliffs offer a prehistoric beauty that fits the spirit of this list.
The real magic happens where these dramatic islands meet the sea. The currents of the Flores Sea create a nutrient-rich environment that supports a staggering amount of marine life, from massive manta rays at Manta Point to sharks, turtles, and enormous schools of fish. The view from the top of Padar Island, with its tri-colored beaches (white, black, and pink), is one of Southeast Asia's most iconic and jaw-dropping vistas.
Pro Tip: The diving in Komodo can be challenging due to strong currents. It's best suited for experienced divers. For snorkelers, spots like the famous Pink Beach offer incredible marine life in calmer, shallower waters.
7. Langkawi, Kedah, Malaysia
Designated a UNESCO Global Geopark, Langkawi is a geological masterpiece. The island is home to some of the oldest rock formations in Southeast Asia, including the magnificent 550-million-year-old Machincang Cambrian Geoforest Park. Here, limestone karsts rise from ancient mangrove forests and turquoise seas.
The best way to appreciate Langkawi’s karst scenery is by taking a boat tour through the Kilim Karst Geoforest Park. You'll glide through winding rivers flanked by sheer limestone cliffs and dense mangroves, spotting eagles, monkeys, and unique geological features. For a different perspective, take the Langkawi Cable Car up to the famous Sky Bridge for a panoramic view of the island's dramatic topography. Nearby Pulau Payar Marine Park offers the best snorkeling and diving in the area.
Pro Tip: Combine the Kilim Geoforest Park tour with a visit to Tanjung Rhu Beach. Its wide, white sands are framed by stunning karst islets you can walk to during low tide.
8. Trang Islands, Thailand
If you're looking for the Krabi of 20 years ago, head south to the Trang Islands. This cluster of quieter, less-developed islands offers all the karst-and-coral beauty with a fraction of the crowds. Islands like Koh Mook, Koh Kradan, and Koh Ngai are laid-back paradises perfect for unwinding.
The most famous attraction here is the Morakot Cave (Emerald Cave) on Koh Mook. To enter, you swim through a pitch-black, 80-meter sea tunnel, emerging into a secret, collapsed sea cave with a perfect white sand beach, enclosed by towering limestone walls. Nearby, Koh Kradan boasts some of the best beaches and healthiest reefs in Thailand, with vibrant coral gardens accessible right from the shore.
Pro Tip: The best way to explore is by hiring a longtail boat for the day to island-hop between Koh Mook, Koh Kradan, and the tiny, uninhabited Koh Chuek for fantastic snorkeling.
9. Bohol, Philippines
Bohol offers a unique twist on the karst-and-coral theme. Its most famous feature, the Chocolate Hills, is an otherworldly landscape of over 1,200 symmetrical, conical karst hills that turn brown in the dry season. It’s a geological wonder that looks completely man-made but is entirely natural.
After exploring these inland marvels and visiting the adorable, big-eyed tarsiers, head to the coast. The adjacent Panglao Island and the tiny nearby Balicasag Island are world-class diving and snorkeling destinations. Balicasag is a marine sanctuary with a stunning coral wall that drops off into the deep blue, attracting massive schools of jackfish, barracudas, and resident sea turtles. It’s the perfect blend of unique terrestrial and marine wonders.
Pro Tip: Stay on Panglao Island for easy access to both the Chocolate Hills and the incredible dive sites. A day trip to Balicasag for snorkeling or diving is an absolute must.
10. Mergui Archipelago, Myanmar
For the true explorer, the Mergui Archipelago is one of Southeast Asia's last frontiers. This chain of over 800 largely uninhabited islands remained off-limits to foreigners for decades, preserving its pristine ecosystems. The islands are a mix of granite and limestone, creating dramatic scenery with hidden coves and white-sand beaches.
The waters here are home to the Moken people, or "sea gypsies," a nomadic seafaring people with a deep connection to the ocean. The reefs are largely unexplored and teeming with life, offering a glimpse of what the Andaman Sea looked like centuries ago. A liveaboard sailing trip is the only way to explore this remote paradise, making it a true adventure off the beaten path.
Pro Tip: Travel to the Mergui Archipelago is still highly regulated and requires booking through an approved tour company, usually on a multi-day liveaboard trip departing from either Myanmar or Thailand.
11. Triton Bay, West Papua, Indonesia
Often called "the next Raja Ampat" or the "last best place," Triton Bay is a remote and breathtakingly beautiful destination for the most intrepid travelers. Located on the southern coast of West Papua, it's even more isolated than Raja Ampat, resulting in an underwater ecosystem that is bursting with life and color.
Triton Bay is particularly famous for its incredible soft corals, which create dazzling underwater gardens of yellow, orange, and purple. The marine life is prolific, with everything from tiny pygmy seahorses to giant whale sharks making regular appearances. Above the water, the karst landscape is just as dramatic as its northern counterpart, with jungle-clad limestone islets rising from misty, calm seas. It’s a truly wild and unforgettable place.
Pro Tip: The main draw for many divers is the resident population of whale sharks that congregate around the local fishing platforms, known as 'bagans'. Interacting with these gentle giants in such a natural setting is a once-in-a-lifetime experience.
From the iconic cliffs of Thailand to the final frontiers of Indonesia, these karst-and-coral islands represent the pinnacle of natural beauty in Southeast Asia. They are destinations that engage all the senses, offering thrilling adventures, serene moments of reflection, and a profound connection to the raw power of our planet.
Each island offers a unique story written in stone and coral, waiting for you to discover it. So, which one will you explore first?
Have you visited any of these islands? Which 'karst-and-coral' paradise is at the top of your list? Share your thoughts and favorites in the comments below!
About the Author
Goh Ling Yong is a content creator and digital strategist sharing insights across various topics. Connect and follow for more content:
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