Ha Long Bay is a UNESCO World Heritage seascape in northeastern Vietnam - an estimated 1,600-2,000 limestone karst islands and islets rising from the emerald water of the Gulf of Tonkin. Toggle the vegetation cap highlight to see which islands hold a green tropical canopy, and the Sung Sot Cave marker to see the bay's tallest island in the scene, standing in for one of its largest caves.
Published figures: core UNESCO World Heritage zone about 1,553 sq km; an estimated 1,600-2,000 limestone islands and islets, about 775 named; karst shaped over roughly the last 20 million years.
Drag to orbit and scroll or pinch to zoom. Everything renders on your device with WebGL.
Ha Long Bay 3D Explorer
This browser explorer shows Ha Long Bay in cross-section: a dense field of steep gray-tan limestone islands rising straight from an emerald water plane, most too sheer to hold more than a cap of green tropical vegetation near the top, with a marker at the bay's tallest island in the scene standing in for Sung Sot (Surprise) Cave.
Ha Long Bay sits in the Gulf of Tonkin off Quang Ninh province in northeastern Vietnam. The name translates to "descending dragon" and is tied to a local folk legend of dragons sent to defend the coast, whose thrashing tails are said to have carved the bay's channels. The limestone islands were shaped over roughly the last 20 million years as tropical rain and sea water dissolved the rock along cracks and fault lines, leaving thousands of steep-sided towers standing apart in the water rather than one connected coastline. The bay has been a UNESCO World Heritage Site since 1994, and its core protected zone covers about 1,553 sq km holding an estimated 1,600-2,000 islands and islets, about 775 of which are named.
- Toggle the vegetation cap highlight to see which islands hold a tropical canopy near the top
- Toggle the Sung Sot Cave marker to see the bay's tallest island in the scene
- Read the area, island count, and karst age figures in the panel
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Figure | Published value |
|---|---|
| Location | Gulf of Tonkin, Quang Ninh province, northeastern Vietnam |
| Core UNESCO zone | about 1,553 sq km |
| Islands/islets | estimated 1,600-2,000, about 775 named |
| Karst age | shaped over roughly the last 20 million years |
| Typical island height | many towers about 50-100 m above the water |
| UNESCO status | World Heritage Site since 1994 |
| Named landmark | Sung Sot (Surprise) Cave, one of the bay's largest caves |
For another scattered island field carved by water, see the Great Barrier Reef 3D Explorer, or compare with a different island-studded sea in the Caribbean Sea 3D Explorer.
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached.
This is an educational approximation - the island field, spacing, and vertical scale are schematic teaching cues, not survey terrain.
Frequently Asked Questions
Where is Ha Long Bay?
In the Gulf of Tonkin off Quang Ninh province in northeastern Vietnam.
How many islands does Ha Long Bay have?
An estimated 1,600-2,000 limestone islands and islets, about 775 of which are named.
How old are the limestone islands?
The islands were shaped over roughly the last 20 million years as rain and sea water dissolved the limestone along cracks and fault lines.
What does "Ha Long" mean?
It translates to "descending dragon", tied to a folk legend of dragons sent to defend the coast.
What is Sung Sot Cave?
Sung Sot, or Surprise Cave, is one of the largest caves in Ha Long Bay, found inside one of its limestone islands.
Is Ha Long Bay a UNESCO World Heritage Site?
Yes. It has been a UNESCO World Heritage Site since 1994, with a core protected zone covering about 1,553 sq km.
Is this a scientific terrain model?
No. It is an educational explorer using published figures - the island field, spacing, and vertical scale are schematic teaching cues, not survey terrain.