Thumb Islet, which we locals call Hon Ngon Tay, is a remarkable, 10-meter-tall limestone pillar that looks exactly like a giant thumb pointing straight up towards the sky. At Vietnamstory, we love to point this special islet out to our Indian guests as “Nature’s blessing” for a successful and happy journey. It has become a wonderful symbol of good luck and is the perfect, quick, and memorable photo opportunity during your cruise through this magical landscape.
The Thumb Islet’s location and how to spot it?
Thumb Islet is strategically located right in the heart of the UNESCO World Heritage site, situated in the beautiful western cluster of the bay. Its prime position makes it a landmark that is very easy to spot on most of the classic cruise routes. Knowing where to look will ensure you don’t miss this charming and iconic formation. Here are the details.
The islet is located approximately 6 km to the Southeast of the Tuan Chau International Marina. It is a primary and much-loved landmark on Cruise Route 2, which is the “Classic” route that includes many of the most famous sights. You can also often see it on certain departures of Route 4 cruises that explore Bai Tu Long Bay.
Thumb Islet stands like a “gatekeeper” near the main path that leads to other famous attractions like Ti Top Island, the beautiful Luon Cave, and the iconic Incense Burner Islet (Dinh Huong). It is important to know that you do not “visit” Thumb Islet in the sense of landing on it. It is a sightseeing-only attraction. Your cruise ship will slow down for about 5 – 10 minutes as it passes by, giving you the perfect opportunity to take photos from the sundeck.
A geological wonder and a symbol of good luck
The islet is a perfect and beautiful silhouette of a human thumb, a natural sculpture that has been shaped by millions of years of time and tide. Its unique shape is a result of a fascinating geological process, and it holds a deep meaning for our local fishermen.
Geologically, it is what is known as a lone, vertical Fenglin karst, which is an isolated limestone tower. Its narrow base and its more rounded, bulbous top create the perfect and unmistakable silhouette of a giant thumb. This incredible formation was created over a period of 20 million years through a process of “marine invasion” and “tropical karstification.” The distinct “thumb” shape is a direct result of the seawater constantly undercutting the base of the limestone over millennia – a process that geologists call marine notching.
For the local fishermen who have sailed these waters for generations, this rock holds a deep reverence. They believe that it represents a reassuring “thumbs-up” from the Sea God, a divine signal that promises calm waters and a bountiful and successful catch. Even today in 2025, it remains a beloved “guardian” figure for all the sailors and travelers who enter the central bay.
READ MORE: Bai Tu Long National Park: Ha Long Bay’s Serene, Untouched Twin
A point of confusion: Thumb Islet vs Finger Islet
Travelers and sometimes even other guides can often confuse Thumb Islet with another similarly named landmark, Finger Islet. While the names are sometimes used interchangeably, it is important to know that they are two distinct and beautiful landmarks located in different parts of the bay. Let’s clear up the confusion so you know exactly what you are looking at.
| Feature | Thumb Islet (Hòn Ngón Cái) | Finger Islet (Hòn Ngón Tay) |
| Location | Ha Long Bay (in the central area, on the classic Route 2) | Lan Ha Bay (in a more remote area, near Cat Ba Island) |
| Height & Shape | Approximately 10–12 meters tall, with a rounded, thumb-like shape. | It is taller and much more slender, looking more like a sharp, pointed spire or an index finger. |
| Symbolism | A symbol of reassurance, good luck, and a “thumbs-up”. | It is seen as a “pointer” or a natural navigational marker. |
| The Vibe | It is an iconic and famous landmark, part of the “Classic” Ha Long tour. | It is a more remote and pristine landmark, part of the “Pristine” Lan Ha Bay tours. |
How to get the perfect shot? Our photography tips
Don’t just take a quick photo of Thumb Islet; capture a fun and memorable story! With a little bit of creativity, you can take a truly special photo here.
- The “Double Thumbs Up” angle: This is the classic and most fun shot to get! Stand on the sundeck of your cruise and align your own hand and thumb with the islet in the background, creating a “double thumbs up.” For the best result, Vietnamstory.in recommends using the portrait mode on your phone (with a 2x or 3x zoom). This will compress the background and make the islet “pop” against the other karsts.
- The best lighting: The Golden Hour (from 4:30 PM to 5:30 PM) provides a beautiful, warm glow that makes the limestone appear to be a stunning bronze color against the emerald water.
- The magic of misty mornings: During our cooler winter months (from December to February), the morning mist often shrouds the bay in a beautiful, mystical layer. At this time, Thumb Islet can look like a giant hand mysteriously emerging from the clouds.
Our tailored tips for a special moment for Indian travelers
At Vietnamstory, we love to ensure that your experience of seeing Thumb Islet is not just a passing glance, but a culturally connected and joyful moment. Here is how we make this moment special for our Indian guests. We love to frame this beautiful islet as nature’s for a successful, safe, and happy adventure through Vietnam. It’s a wonderful and positive way to start your journey into the bay.
Most of our cruises will pass by Thumb Islet between 12:30 PM and 1:30 PM, which is often just as you are finishing your delicious, Indian-style vegetarian buffet lunch. Our expert guides will always make an announcement, so you don’t miss the sighting while you are enjoying your Dal Tadka!
This is a great and interactive spot for children. We love to encourage the kids to “name” the other interesting rock formations nearby, turning the cruise into a fun “rock gallery” scavenger hunt.
READ MORE: Is Ha Long Bay Worth Visiting in 2026?
Your practical visitor information for 2026
Here are the final details you need to know. Let’s answer your most common practical questions.
- Can you climb it? No. To preserve the fragile karst formation and for everyone’s safety, landing on or climbing the islet is strictly prohibited.
- Is it near Ti Top Island? Yes, it is very close, only about 1–2 km away. It is often the last major and interesting landmark you will see just before your cruise arrives at the beautiful Ti Top beach.
- Is it included in Day Trips? Yes, almost all of the popular 6-hour and 8-hour day cruises that depart from the Tuan Chau Marina will pass by this iconic islet.
- Best season: The best time to see the islet is from October to April. The clear skies and high visibility during our dry season make the unique “thumb” shape easily recognizable from a distance.
- Recommended equipment: For keen photographers who want to capture the detailed marine erosion marks and the beautiful textures on the rock face, a zoom lens (like a 70-200mm) is highly recommended.
Conclusion
As your cruise boat navigates deeper into the heart of Ha Long Bay, the sight of Thumb Islet serves as a perfect and friendly welcome. It is like a natural gateway, a reassuring gesture from the bay itself, signaling that you are entering a place of wonder and that your journey will be a good one. For the first-time visitor, this simple, recognizable, and positive landmark provides a wonderful sense of orientation and a feeling of being warmly greeted by the very landscape you have come so far to see. Let Vietnamstory be the first to welcome you to this incredible destination. We can plan every detail of your cruise, ensuring you see all the most iconic and beloved sights, like the lucky Thumb Islet. Get in touch with us to plan your trip, and get ready to receive the warmest of welcomes from the natural wonders of Vietnam.