Dao Ngoc Xanh (Phu Tho): A Traveler's Guide to the Green Gem Island

What Dao Ngoc Xanh actually is

Dao Ngoc Xanh sits on a reservoir island in Thanh Thuy district, Phu Tho province, roughly 80 km west of Hanoi. The name translates to "Green Gem Island," and while that sounds like resort marketing, it's a fair description — a hilly island covered in fruit orchards and secondary forest, surrounded by the calm water of the Ngoi Lao 2 reservoir system.

The area was developed for eco-tourism in the mid-2010s, built around what Thanh Thuy district is actually known for: natural hot springs. The underground thermal water here runs 37-42°C and has been used by locals long before anyone put up a ticket booth. The island itself is small enough to walk around in a couple of hours, which is part of the appeal. This isn't a theme park. It's a low-key overnight destination where Hanoians go when they want green space without driving to Sapa or Mai Chau.

Why travelers go

Most visitors are domestic — weekend families, couples, small groups from Hanoi (하노이 / 河内 / ハノイ) looking for a one-night escape. Foreign travelers are rare here, which means prices stay honest and nobody's trying to sell you a tour package.

The draw is simple: hot spring soaking, lake views, cycling on empty roads, and a pace that's deliberately slow. Thanh Thuy district also sits at the edge of the Muong cultural area, so the food leans toward upland flavors — grilled stream fish, bamboo-tube rice, wild fern stir-fries. If you've been eating "[pho](/posts/pho-vietnam (베트남 / 越南 / ベトナム)-noodle-soup-guide)" and "banh mi" for a week straight in Hanoi, the change is welcome.

Best time to visit

The sweet spot is October through March. The cool, dry weather makes the hot springs feel like the point rather than an afterthought — soaking in 40°C water when it's 35°C outside is less fun than it sounds.

• November to January: Best months. Cool mornings (12-18°C), low humidity, clear skies over the reservoir. Weekdays are nearly empty.
• February to March: Still pleasant, but weekends around Tet and the Hung Kings Festival (usually mid-April, but preparation starts early in Phu Tho) can bring crowds. Phu Tho is the spiritual heartland of the Hung Kings Festival — Den Hung temple complex is only about 30 km north of Thanh Thuy — so if your timing overlaps, that's worth a half-day side trip.
• May to September: Hot, humid, afternoon rain. The reservoir is at its fullest and greenest, but outdoor activities get uncomfortable by midday.

How to get there from Hanoi

Dao Ngoc Xanh is about 80 km from central Hanoi, heading west on the Hanoi-Hoa Binh expressway (QL6/CT.08) before cutting north toward Thanh Thuy.

By motorbike or car: The most practical option. Figure 2-2.5 hours depending on traffic getting out of Hanoi. The route through Xuan Mai and Ba Vi district is straightforward. If you're on a motorbike, fill up before leaving the QL6 corridor — petrol stations get sparse in the last 15 km.

By bus: Catch a bus from My Dinh bus station toward Thanh Son or Thanh Thuy. Tickets run 60,000-80,000 VND. Buses drop you in Thanh Thuy town, from where you'll need a local xe om (motorbike taxi) for the last 5-7 km to the island area — expect 30,000-50,000 VND.

By private car/taxi: A one-way Grab or private car from Hanoi runs roughly 800,000-1,200,000 VND depending on the vehicle. Not cheap, but splits well among four people.

Photo by Quang Nguyen Vinh on Pexels

What to do

Soak in the hot springs

This is the main event. Several resorts and public bathing spots in the Thanh Thuy area pipe natural thermal water into pools. Temperatures hover around 38-42°C. Public bathing access costs 50,000-150,000 VND depending on the facility. The water has a mild mineral smell — nothing sulfuric — and locals swear by it for joint pain. Even if you're skeptical, an evening soak after the drive from Hanoi is hard to argue with.

Cycle or walk the island loop

The island and surrounding reservoir paths are flat to gently rolling — maybe 8-10 km of rideable trails total. Most guesthouses lend or rent bicycles for 50,000-80,000 VND per day. Morning rides before 9 AM are best: mist over the water, birdsong, almost no other people. The orchards along the route grow longan, jackfruit, and guava depending on season.

Visit the fruit orchards

Thanh Thuy is an agricultural district, and several orchards near the island let visitors pick fruit directly (longan season is July-August, guava is more or less year-round). It's informal — you walk in, pick, weigh, pay. Prices are usually 30,000-50,000 VND per kilogram.

Take a boat on the reservoir

Small boats and kayaks are available for 100,000-200,000 VND per hour. The reservoir is calm, not wide, and ringed by low green hills. Sunset from the water is genuinely good — no qualifier needed.

Day-trip to Den Hung

The Hung Kings Temple complex (Den Hung) is about 30 km north, reachable in under an hour. It's the site of the Hung Kings Festival and one of the most culturally significant religious sites in northern Vietnam. Entry is 10,000 VND. Go early to beat school groups.

Where to eat nearby

Thanh Thuy doesn't have a restaurant scene, but the local food is solid.

"Com lam" (bamboo-tube rice) is the signature — sticky rice cooked inside a bamboo section over charcoal. It's served at most local eateries and pairs with grilled pork or chicken. A full meal runs 80,000-120,000 VND per person.

Grilled stream fish — usually small carp or tilapia from local ponds, grilled over charcoal with turmeric and dill, similar to Hanoi's "cha ca" but rougher, served with fresh herbs and rice noodles. Look for small family restaurants along the road approaching the island — the ones with plastic chairs and smoke coming from the back are usually the right call.

Where to stay

• Budget homestays: 300,000-500,000 VND per night. Basic rooms, fan or AC, shared hot spring pools. Clean but no-frills.
• Mid-range resorts: 800,000-1,500,000 VND per night. Private hot spring tubs, lake-view rooms, breakfast included. Thanh Lam Resort and a few others cluster near the island.
• Higher-end options: A couple of newer properties push toward 2,000,000-3,000,000 VND with villa-style accommodation. Fine for a special occasion, but honestly the mid-range places deliver most of the experience.

Book directly by phone if possible — rates on booking apps are often 15-20% higher here.

Photo by Thuan Pham on Pexels

Practical tips locals would tell you

• Bring cash. Card acceptance is almost nonexistent outside the larger resorts. ATMs exist in Thanh Thuy town but can run empty on weekends.
• Weekdays are dramatically better. Saturday night the hot spring pools get crowded with Hanoi families. Tuesday? You'll have the water to yourself.
• Mosquitoes are real, especially near the reservoir at dusk. Bring repellent.
• Phone signal is fine (Viettel and Mobifone both cover the area), but don't expect fast data speeds everywhere.

Common mistakes to avoid

• Treating it as a day trip. You can technically drive from Hanoi and back in a day, but it defeats the purpose. One night minimum lets you actually use the hot springs, eat properly, and decompress.
• Showing up on a holiday weekend without booking. Tet (뗏 (베트남 설날) / 越南春节 / テト (ベトナム旧正月)), Hung Kings Festival, and September 2 long weekends fill the area fast. Book at least two weeks ahead.
• Expecting a tropical island. This is a freshwater reservoir island in the midlands, not Phu Quoc (푸꾸옥 / 富国岛 / フーコック). Calibrate expectations and you'll enjoy it far more.

Practical notes

Dao Ngoc Xanh works best as a quiet weekend addition to a northern Vietnam loop — pair it with a stop in Ninh Binh (닌빈 / 宁平 / ニンビン) or a ride through the Ba Vi hills. It's not a destination you'd fly across the world for, but if you're based in Hanoi and tired of the usual suspects, it's an honest 36-hour reset.