Thien Canh Son Cave in Halong Bay

Thien Canh Son Cave (Hang Co) is a dry cave about 40 meters up the side of Hon Co island, in the Cong Do area of Ha Long Bay, near Bai Tu Long Bay. Only boats get there. The visit takes about an hour, which makes it a good stop on a cruise rather than a trip of its own.

The stunning and glorious caves are the most outstanding feature of Halong Bay. With thousands of islands and hundreds of limestone caves, Halong Bay is like a natural museum where tourists can learn more about geology and biology. When mentioning the most stunning caves in Halong Bay, tourists will list many well-known caves such as Sung Sot Cave, Dau Go Cave, Trinh Nu Cave and Thien Canh Son Cave. As its name suggests, Thien Canh Son Cave offers tourists with the impressive beauty like a fairy land.

Location of Thien Canh Son Cave

Thien Canh Son Cave is in the Cong Do area, on Hon Co island, about 14 kilometers by boat from Ha Long International Cruise Port and 19 kilometers from Tuan Chau International Marina. Locals named the cave “Hang Co” after the island, the Ha Long Bay management board says. Later, its beauty inspired the name “Thien Canh Son.”

Is Thien Canh Son Cave in Ha Long Bay or Bai Tu Long Bay?

Bai Tu Long Bay and Halong Bay are neighbors, and cruise companies often sell Cong Do under the Bai Tu Long Bay name. Officially, the cave is in Halong Bay: it is on Route 4 of the Ha Long Bay management board, which has described the Cong Do area as part of the heritage site’s core zone. Halong Bay is a UNESCO World Heritage site, listed with the Cat Ba archipelago since 2023. Coming to Bai Tu Long Bay, tourists should not ignore the area of Cong Do.

Not only does this area have a diverse system of flora and fauna but also includes a large number of impressive caves.

History of Thien Canh Son Cave

Thien Canh Son Cave formed over millions of years through limestone erosion and deposition. Water eroded calcium crystals in the limestone, which then combined to create stalagmites and stalactites.

The cave was originally called “Hang Co” because it sits on Hon Co Island. “Thien Canh Son” means “mountain with a view of fairy land,” a fitting name for such a stunning place.

Highlights of Thien Canh Son Cave

When thinking of a cave in Halong Bay, you might imagine one at the waterline, entered by boat. Thien Canh Son Cave is different. It sits on a slope of Hon Co island, about 40 meters above sea level. The narrow path winds under ancient trees, with green grass growing between the steps.

Stepping inside, a breathtaking world unfolds. Stalactites and stalagmites cover both the ceiling and floor, built up over millions of years of erosion and deposition. The formations vary in size and shape, each unique. Together, they create a dazzling display of colors and textures.

The cave feels like a fairy-tale realm. Stalactites hang like Gothic chandeliers. Some stalagmites resemble flowers and animals, while others look like statues. Their lifelike presence sparks the imagination. It feels as if they hold stories whispered for thousands of years.

Inside, the temperature stays cool, no matter how hot it is outside. Fresh air fills the space, offering relief from the heat. The cave’s peaceful atmosphere washes away stress, allowing visitors to fully admire its beauty.

What to See and Do at Thien Canh Son Cave?

1. Discovering the cave

Thien Canh Son’s beauty has made it a popular destination. Soft lighting enhances the cave’s natural charm without overpowering its natural appeal.

The entrance is narrow, but the floor inside is flat. On sunny days, daylight comes in through cracks in the ceiling.

2. Admiring the view of Bai Tu Long Bay from above

After exploring the cave, step outside for a panoramic view of Bai Tu Long Bay. From this height, the bay appears even more stunning, with its limestone islands resembling scattered gems on the water.

Around the cave, wild plants thrive despite harsh conditions. Their colorful flowers add to the cave’s charm.

3. Kayaking, but No Swimming

At the foot of Thien Canh Son Cave there is a strip of white sand, but it is not a licensed swimming beach: in July 2026, Tien Phong reported Ti Top as the only swimming beach in operation on Ha Long Bay. Don’t plan to swim here.

For a more adventurous experience, rent a kayak to explore the islands around Hon Co: the management board’s Route 4 page lists a kayak service at the cave. This isolated island offers an unspoiled glimpse of nature.

How Hard Is the Climb to Thien Canh Son Cave?

A stone stairway climbs about 40 meters from the beach to the cave mouth. Published guides and tour pages give anything from about 100 to 400 steps, so don’t plan around a count. With bad knees or a small child to carry, ask the cruise company whether you can wait on the beach. Allow about an hour: our 3-day cruise schedules the cave from 7:30 to 8:30 a.m.

How to Get to Thien Canh Son Cave?

Thien Canh Son Cave is reached only by boat. To visit, take Route 4 (VHL4), one of the management board’s official sightseeing routes, which departs from Tuan Chau International Marina. This route includes stops at Vung Vieng Fishing Village and Hang Thay.

Overnight boats on Route 4 anchor in the Cong Do area, so the cave is an easy morning stop. Two of our cruises include it: the 2-day Swan Cruise trip and the 3-day Bai Tu Long Bay cruise.

If you have more time for your vacation, you should consider an overnight trip in Halong Bay, which will allow you to explore more interesting things of Halong Bay when the night falls.

>>> See more: Ha Long Bay tours and cruises

Thien Canh Son Cave Ticket Price (2026)

There is no separate ticket for the cave. You pay the Route 4 sightseeing fee: 200,000 VND per person for a day trip, or 500,000 VND for one night aboard and 650,000 VND for two, according to the management board’s fee table. Children under 1.2 meters or under 7 go free, and those from 7 to under 16 get 20% off. The boat costs extra, though a cruise package may include the fee.

Extra Tips

• The best time to go on a cruise in Halong Bay is spring, roughly March to April, and from October to December. The weather in Halong Bay at this time is nice enough for you to take part in outdoor activities. Summer and early autumn bring storms: tourist boats on the bay stopped on 20 July 2025 for Storm Wipha, and after Typhoon Yagi in September 2024 the bay’s sightseeing routes did not reopen until 13 September, so leave spare days.
• The tourism season in Halong Bay might be very crowded, so you need to book your tour and hotel in advance.
• Remember to prepare all your necessary belongings, including shoes with a good grip for the steps, sunscreen, hat and sunglasses.
• If you hire a kayak to row yourself, you need to follow the safety instructions and wear a life-jacket to ensure your safety.
• Don’t start your journey on a rainy day. The path leading to Thien Canh Son Cave in wet weather conditions can be extremely slippery, so you had better go on a nice day.
• Remember to protect the environment in the area of Thien Canh Son Cave. This area is a natural reserve, so you need to join hands to preserve the living environment of wild species in Cong Do Island.

Sources: Ha Long Bay – Yen Tu World Heritage Management Board, sightseeing fees (updated March 2025); fee exemptions (updated November 2024) and visiting hours (updated November 2024); Tien Phong, Ha Long Bay swimming beaches, 28 July 2026; VTC News, boats stopped for Storm Wipha, 20 July 2025