Ang Thong Marine Park
Forty-two limestone islands and a saltwater lake held inside a collapsed crater, an hour north-west of Samui. We go by private boat, ahead of the ferries.
Where
Surat Thani
Best time
The Gulf's settled months run roughly February to September — the reverse of the Andaman.
Ang Thong means golden bowl, and the archipelago is forty-two islands of limestone and jungle scattered across a shallow shelf north-west of Samui. Almost all of them are uninhabited. They rise steeply — cliff straight out of the water, a thin crown of forest, and beaches that exist in pockets between the rock rather than in continuous runs.
Two things bring people here. On Koh Mae Ko there is a body of seawater held inside a collapsed crater, connected to the sea only through fissures in the rock beneath it, a green that does not photograph accurately. On Koh Wua Talap, where the park headquarters sits, a staircase and then a scramble climbs to a headland with the whole archipelago laid out below.
Alex Garland used the idea of a hidden lagoon here in The Beach, which is why more people arrive expecting a swim than the park permits.
The Emerald Lake is not for swimming
Thale Nai sits inside a collapsed cave system on Koh Mae Ko: a ring of cliff with water at the bottom of it that exchanges with the open sea through the limestone rather than by any visible channel. The colour comes from depth, algae and the light coming over the rim, and it shifts through the day.
Swimming in it is prohibited and has been for years. The water body is small, the exchange is slow and it does not recover from use. What you do instead is climb the boardwalk and steps to the platform on the crater rim, which takes about ten minutes and delivers the view the lake is famous for.
The climb on Koh Wua Talap
The viewpoint above the park headquarters is around five hundred steps and then a section of bare limestone where the handrail becomes a rope and the rock is sharp enough to take skin off a palm. It is a genuine scramble rather than a stroll, and it is hot by nine.
At the top the archipelago opens out in both directions, islands stacked to the horizon in flat green water. It is the single best view in the Gulf, and the argument for going first. Below it, the headquarters beach holds the park's only accommodation — a few basic bungalows and a camping ground — which is how a small number of people manage to be up there at sunrise.
Why the Gulf's season is the reverse of the Andaman's
Thailand's two coasts run on different monsoons, and it is the most useful piece of planning knowledge in the country. The Andaman takes the south-west monsoon from roughly May to October; the Gulf takes the north-east, which runs through November and December and sometimes into January.
So the months that close the Similan Islands are often the settled months out here, and the reverse holds too. The practical consequences at Ang Thong are specific: the park is generally at its best from around February to September, and it normally closes for part of November and December when the sea is up. A journey in the Andaman's wet months that still wants islands should be looking at the Gulf.
How We Visit
Our way in
We go by private boat from Samui or Koh Phangan rather than on the scheduled catamaran, which changes two things: we leave early enough to be first on the Koh Wua Talap climb, and we can change the plan if the wind has turned overnight. A longtail suits a slow day among the inner islands; a speedboat suits a party that wants the crater lake, the viewpoint and an hour in kayaks without a long day at sea. Lunch is aboard, at anchor in a bay, rather than in the queue at the headquarters canteen.
Questions
What travellers ask
Can you swim in the Emerald Lake at Ang Thong?
No. Swimming in Thale Nai, the saltwater lake on Koh Mae Ko, is prohibited. It is a small body of water inside a collapsed crater that exchanges with the sea only through the rock, so it does not recover from use. Visitors climb a boardwalk and a flight of steps to a platform on the crater rim instead, which takes about ten minutes and gives the view the lake is known for.
Was The Beach filmed at Ang Thong?
No. Alex Garland set the novel's hidden lagoon in this archipelago, and the crater lake on Koh Mae Ko is the obvious source of the idea, but the film was shot at Maya Bay on Phi Phi Leh, on the other coast of the country. Ang Thong is where the idea came from; Maya Bay is what was put on screen, and the two are several hundred kilometres apart.
When is the best time to visit Ang Thong Marine Park?
Roughly February to September, which is the Gulf's settled stretch and the reverse of the Andaman's. The park normally closes for part of November and December, when the north-east monsoon puts a sea up and the crossing becomes unreliable. That opposite cycle is useful to know: if your dates fall in the Andaman's wet months, the Gulf is usually the better half of the country to be on.
Journeys That Include This
Ask about Ang Thong Marine Park
It sits inside a journey we already run, and it fits just as easily into one written from scratch around your dates.
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