Ang Thong Marine Park from Koh Phangan - a guide to the 42 islands, the green lagoon and the viewpoints

What is Ang Thong Marine Park?

Ang Thong, officially Mu Ko Ang Thong National Marine Park, is a national marine park in the Gulf of Thailand, west of Koh Samui and south-west of Koh Phangan.

The park covers a group of about 42 islands, most of them uninhabited. The scenery is defined by limestone cliffs rising out of the sea, dense tropical vegetation, small bays and white beaches.

Unlike beach trips where the main attraction is swimming in the sea, Ang Thong offers an experience that combines several kinds of scenery and activity in one day.

You can sail between the islands, go kayaking, climb to viewpoints, visit a lagoon surrounded by cliffs and spend time on the beach.

The trip particularly suits anyone who loves nature and dramatic scenery and is happy to add a little physical activity.

How to get to Ang Thong from Koh Phangan

The usual way to get to Ang Thong is on an organised boat trip.

Trips from Koh Phangan usually leave from the Thong Sala area, and sometimes include a hotel pick-up and a transfer to the departure point.

There's no regular public ferry to the park like the ferries linking Koh Phangan, Koh Samui and Koh Tao.

You can book a group tour, and in some cases a private boat with a captain.

The main options are:

• Speedboat tour: suits anyone who wants to get there faster and spend more of the day on activities in the park. On the other hand, in choppy seas the ride can be bumpy.
• Big-boat tour: may be more comfortable if you prefer a slower crossing, but there are fewer routes available from Koh Phangan than from Koh Samui.
• Private tour: gives you more flexibility over the route and stopping times, but is usually considerably more expensive.

Before booking, make sure the trip really leaves from Koh Phangan and not from Koh Samui. Not every trip that appears in search results includes the transfer between the islands.

What does an Ang Thong day trip include?

The route varies between companies, but a typical day trip may include:

• Sailing between the park's islands.
• A snorkelling stop.
• A visit to Mae Koh island and the viewpoint over the green lagoon.
• Lunch.
• A stop on Wua Ta Lap island, home to one of the famous viewpoints.
• Free time on the beach.
• Kayaking, if it's included in the package.

The whole trip from Koh Phangan usually takes about seven to nine hours, including some of the transfers and crossings.

Bear in mind that not every route fits in all the activities. Some companies spend more time on kayaking, others on the viewpoints, and on some routes snorkelling is a bigger part of the day.

The green lagoon - Emerald Lake on Mae Koh

One of the attractions most closely associated with Ang Thong is the green lagoon, known as Emerald Lake or Thale Nai.

The lagoon is on Koh Mae Koh, and it's actually a saltwater lake surrounded on almost all sides by limestone cliffs and dense vegetation.

What makes it special is its location: a large body of water hidden inside the island, with green rock walls rising all around it.

To see the lagoon from above, you climb a stepped trail to a viewpoint.

Is the climb to the lagoon hard?

The climb is fairly short, but some of the steps are steep.

For travellers with reasonable fitness it's usually manageable, but in the heat and humidity it can be strenuous.

Wear comfortable shoes that don't slip, take water and climb at a pace that suits you.

The view from the top is one of the main reasons to visit.

Can you swim in the lagoon?

No. The lagoon is a protected nature area, and you visit it from the designated viewpoints.

The green water may look inviting, but it's not a swimming stop.

If you want to swim, you can do so at other stops on the trip, depending on conditions and the crew's instructions.

The Koh Wua Ta Lap viewpoint - the famous view of the 42 islands

If there's one picture associated with Ang Thong, it's usually the one taken from the high viewpoint on Koh Wua Ta Lap.

From the viewpoint you can see the green islands scattered across the sea, some small and round, others long and pointed, with limestone cliffs rising above the water.

It's one of the most remarkable views in the Gulf of Thailand.

But be aware: getting to the viewpoint isn't a gentle stroll along a promenade.

How hard is the climb to the viewpoint?

The trail up is a few hundred metres long, but it's steep and takes effort.

In places you walk over steps, rocks and roots, and sometimes use ropes and railings.

Along the way there are rest points and viewpoints at different heights.

Many travellers say the climb was harder than they expected, mainly because of the heat and humidity.

Our advice is to wear shoes with good grip, drink plenty of water and not try to reach the top at all costs.

If you have knee problems, difficulty with balance or trouble walking on uneven surfaces, think about whether the trail is right for you.

Do you have to go all the way to the top?

Not necessarily.

There are lovely viewpoints along the way too, and you can decide to stop before the summit.

If you don't want to climb, you can stay on the beach, rest and enjoy the view from sea level.

That said, if you're going to Ang Thong mainly for the viewpoints, choose a route that allows enough time to climb up and come back down.

Kayaking in Ang Thong - is it worth it?

Kayaking is one of the activities that sets Ang Thong apart from other island trips.

Instead of watching the cliffs only from the tour boat, you can get close to them at water level, paddle along rock walls and discover small bays from a different angle.

The experience suits anyone who enjoys moderate activity in nature, but how hard it is depends on the route, the wind and the state of the sea.

On some trips kayaking is a guided activity, and on others it's a paid extra.

Do you need kayaking experience?

On calm, guided routes previous experience isn't always required, but you need to feel comfortable in the water and follow the guides' instructions.

Wear a life jacket and stay within the area set for the activity.

If the weather isn't suitable, the operator may cancel the kayaking even if the rest of the trip goes ahead.

Snorkelling in Ang Thong - is it really good?

This is where it's important to manage expectations.

Many tour companies present snorkelling as one of the main activities in Ang Thong, but travellers' reviews are mixed.

Some travellers enjoyed the snorkelling and saw colourful fish, while others report limited visibility, areas crowded with boats and a snorkelling experience less impressive than they'd expected.

Visibility is affected by sea conditions, sediment in the water, the season and the spot where the boat stops, among other things.

So we wouldn't choose an Ang Thong trip for the snorkelling alone.

Ang Thong or Koh Tao - where's better for snorkelling?

If your main aim is to see fish, coral and a rich underwater world, look at snorkelling trips on Koh Tao and Koh Nang Yuan.

If your aim is to enjoy striking island scenery, a unique lagoon, viewpoints and kayaking, Ang Thong offers a completely different experience.

It's not a question of which destination is more beautiful, but of what you're looking for from your day out.

The beaches of Ang Thong - is there time for a swim?

On some routes you stop at a beach on Wua Ta Lap island or at other beaches open to visitors.

You can rest on the sand, go into the water in permitted areas and enjoy the view of the cliffs and islands.

But remember that an organised trip runs to a fixed timetable.

If the route also includes two viewpoints, kayaking and snorkelling, there may not be much time left for lazing on the beach.

If you're mainly after a day of swimming and relaxing on a tropical beach, you may prefer another trip from Koh Phangan, such as a boat trip to Bottle Beach.

What do travellers say about Ang Thong?

Reading travellers' reviews, a few main themes keep coming up.

The scenery is the highlight

Many describe the islands and the viewpoints as the most impressive part of the day.

The view from above, with dozens of green islands poking out of the sea, is one of the main reasons people recommend the park.

The climb to the viewpoint is harder than expected

Travellers warn not to underestimate the trail just because it's fairly short.

The gradient, the heat and the uneven surfaces make the climb a real effort for some visitors.

The snorkelling doesn't always live up to expectations

This is one of the topics where opinions are especially divided.

Some enjoyed it, while others were disappointed by the visibility and the crowds at the snorkelling sites.

The weather has a big effect on the experience

On a calm sea and a clear day the crossing can be pleasant and the views especially impressive.

In strong wind or choppy seas, the crossing can be less comfortable, and sometimes some activities are changed or cancelled.

Not every organised trip is the same

Even when the destination is the same, the experience can vary with the number of participants, the type of boat, the guides and the time allowed at each stop.

So read reviews about the specific operator and its route, not just about the park in general.

How much does an Ang Thong trip from Koh Phangan cost?

Trip prices vary with the company, the type of boat, the number of participants and the activities included.

Based on offers published during 2026, you can find speedboat day trips from Koh Phangan for around 1,900-2,400 baht (about $57-71 / €50-63) per person, and there are also more expensive packages.

For example, one company advertises a day trip for 2,200 baht (about $65 / €58) per adult, not including the park entrance fee.

Many offers list the entrance fee for foreign visitors to the park's main areas as 300 baht (about $9 / €8) per adult and 150 baht (about $4 / €4) per child.

Check the current price and what the package includes before you pay.

What should you check in the price?

• Is the park entrance fee included?
• Is there a hotel pick-up and drop-off?
• Are the kayaks included in the price?
• Is snorkelling gear provided?
• Are lunch and drinks included?
• How many people are likely to be on the boat?
• What is the cancellation policy in case of bad weather?

If you're staying on a remote beach on Koh Phangan, also check whether there's a surcharge for the transfer.

When is the best time for an Ang Thong trip?

In the Gulf of Thailand the weather differs to some extent from Phuket and Krabi, which are on the Andaman Sea side.

In general, January to April is considered a fairly good time for boat trips around Koh Phangan and Koh Samui.

That said, even at this time of year there can be days with wind, rain and choppy seas.

Is the park open all year?

No.

Ang Thong closes seasonally for safety and conservation reasons, mainly during the monsoon.

According to the official website of the Thai national parks authority, the usual annual closure is 1-30 November, but other sources mention closures of key sites in the park until mid-December.

So it's especially important to check the park's official notice for the date you're planning to visit.

Even when the park is open, boat operators may cancel a departure because of unsuitable sea conditions.

Should you book the trip in advance?

If you're coming in a busy season and want a particular trip, check availability in advance.

On the other hand, for a trip so dependent on the weather, it's important to stay flexible.

If you're spending a few days on Koh Phangan, don't schedule Ang Thong for your last day.

That way, if it's cancelled because of the weather, you may be able to move the trip to another day.

Before booking, read recent reviews of the company, especially about how the day is organised, crowding on the boat, safety and the length of the stops.

What to bring on an Ang Thong trip

• Swimwear and a towel.
• Closed shoes or walking shoes with good grip for the viewpoints.
• Sandals suitable for the beach and the boat.
• Sunscreen, a hat and sunglasses.
• A waterproof bag for your phone and valuables.
• Drinking water.
• Dry clothes to change into.
• Cash for entrance fees or other expenses.
• Seasickness medication if you need it, following medical advice.

If you're planning to climb to the high viewpoint, don't make do with flip-flops. Your shoes can make a big difference to comfort and safety.

Ang Thong or Koh Nang Yuan - which trip should you choose from Koh Phangan?

The two trips offer different experiences.

Ang Thong mainly suits anyone looking for dramatic island scenery, a unique lagoon, high viewpoints and kayaking.

Koh Nang Yuan and Koh Tao particularly suit anyone interested in beaches, snorkelling and clear water, depending on sea conditions.

If you love photographing scenery, hiking and discovering special places, Ang Thong may be the more interesting choice.

If you'd rather spend a lot of time in the water snorkelling, look at trip options to Koh Tao first.

And if you have enough days on Koh Phangan, there's no reason not to combine both kinds of experience.

The full Koh Nang Yuan guide →

Is Ang Thong suitable for families with children?

The trip can suit families, but consider your children's ages and the level of activity.

The crossing can be fairly long, and the climb to the viewpoints involves steep steps and strenuous sections.

Families with young children can choose to stay on the beach while part of the group climbs to the viewpoint, if the timetable and the crew allow it.

Check in advance the boat operator's age restrictions, the availability of suitable life jackets and the conditions for joining the kayaking and snorkelling.

Can you visit Ang Thong independently?

There's no regular public ferry to the park that lets you explore it independently as you would an inhabited island.

That said, you can look into hiring a private boat with a captain from a licensed operator.

The advantage is being able to plan a more tailored route, choose the order of the stops and spend more time on the attractions that interest you.

The drawback is the relatively high price.

Even on a private trip you must follow the park's rules, opening hours and weather conditions.

So is an Ang Thong trip worth it?

If you love remarkable scenery, green islands, limestone cliffs and spectacular viewpoints, the trip is well worth considering.

What makes Ang Thong special isn't just its beaches, but the combination of dramatic sea scenery with activities you can do throughout the day.

The green lagoon, the Wua Ta Lap viewpoint and kayaking are the main reasons to choose this trip.

On the other hand, if you're mainly expecting exceptional snorkelling or a day lazing on one beach, you may enjoy a different trip more.

Our advice is to choose the trip by the attractions that matter to you, not just by the number of stops listed in the itinerary.

Before booking, make sure the route includes the lagoon and the main viewpoint, check how much time is allowed for each, and choose a day when sea conditions are suitable.

That way you can enjoy one of the most remarkable landscapes in the Gulf of Thailand without arriving with the wrong expectations.

Ang Thong FAQs

How many islands are there in Ang Thong?

The park has about 42 islands, but a standard day trip visits only a few of them.

How long does the trip from Koh Phangan take?

Usually about seven to nine hours, including some of the transfers and crossings. The exact length depends on the company and the route.

Do you have to climb to the viewpoints?

No. You can stay on the beach, but the viewpoints are among the park's main attractions.

Can you swim in the green lagoon?

No. The lagoon is a protected area, and you view it from the viewpoints.

Is the snorkelling in Ang Thong recommended?

Opinions are divided. The quality of the snorkelling varies with sea conditions and visibility. If you're going mainly for the snorkelling, compare trips to Koh Tao as well.

Can you get to Ang Thong from Koh Samui?

Yes. There are day trips from Koh Samui too, and the choice is sometimes wider.

Can you stay overnight in the park?

There are basic accommodation options run by the park, subject to availability, permits and whether the park is open. If you're interested in staying, check in advance with the park or a licensed operator.

Is November a good time to go?

November is a particularly problematic month because of the monsoon and the seasonal closures. Check the park's status before planning your visit.

Editor's note: this guide is based on tourist information, operators' published material and travellers' reviews. The photos were provided by a photographer who visited the park, with permission to use them on this site. It is not an account of a personal visit by our editorial team.