Ask most visitors on Koh Samui which boat day to book and it comes down to Ang Thong or Pig Island. They are very different days. One goes west to Mu Ko Ang Thong National Marine Park, a protected archipelago of limestone islands with a famous viewpoint and an inland saltwater lake. The other goes south to Koh Tan and Koh Madsum (Pig Island), with shorter hops and a day built around swimming, snorkelling and time on deck.
Both are good trips. They suit different people, different fitness levels and different times of year. Below are the differences that count, so you can pick the trip that fits your group rather than the one with the loudest flyer.
Quick facts
| Ang Thong National Marine Park | Pig Island catamaran (Five Islands, Koh Tan, Koh Madsum) | |
|---|---|---|
| Where | About 30 km west of Koh Samui, with 42 islands in a protected national park | Off Koh Samui’s south and south-west coast |
| Main draws | Viewpoint over the archipelago, Emerald Lake, kayaking among cliffs | Snorkelling and water toys at Koh Tan, the beach pigs on Koh Madsum, Five Islands rock formations |
| Effort level | Moderate to high if you climb the viewpoint (steep trail with ropes) | Low. Nothing to climb, and everything happens from the boat or the beach |
| Typical day | Roughly 6–8 hours, depending on operator and boat | Samui Journey: hotel pickup 9:00–9:40 AM, back at your hotel around 4:30 PM |
| Extra fees | National park entrance fee, paid separately unless your tour includes it | None on the Samui Journey catamaran (the Pig Island landing fee is included) beyond personal spending and optional tips |
| Seasonal closure | Usually closed 1 November to 15 December each year | No fixed closure; each departure depends on daily sea conditions |
| Best for | Hikers, landscape photographers, kayakers | Families, mixed-ability groups, anyone who wants an easy day on the water |
Ang Thong or Pig Island? Which one to pick
Choose Ang Thong if you want big scenery, are happy to climb a steep trail in the heat, and see the boat ride mostly as transport to the islands.
Choose the Pig Island catamaran if you want the boat itself to be part of the fun, are travelling with children or non-hikers, or would rather have a lazy day of swimming, snorkelling and lunch at sea.
If you have the time, do both on separate days. They show you very different sides of the Gulf of Thailand.
What an Ang Thong day looks like
Ang Thong became a national park in 1980. It covers about 102 square kilometres of sea and islands and is also a listed Ramsar wetland. The islands are steep limestone, full of caves, sinkholes and marine lakes, and you visit with a licensed tour operator.
The Emerald Lake
On Koh Mae Ko, a short, steep trail leads to a viewing platform above Thale Nai, a saltwater lake surrounded by cliffs and linked to the sea by underground passages. It is a striking sight, but you can’t swim in the lake, so think of it as a viewpoint, not a swim stop.
The viewpoint climb
The view on all the postcards is from Koh Wua Ta Lap, where a steep trail of roughly 500 metres climbs to a lookout over the archipelago. The independent Thai National Parks guide mentions rope-assisted sections and puts the climb at around 25–30 minutes. Reasonably fit adults in proper shoes will manage, but it is hot, rocky work. Small children, anyone with bad knees and anyone in flip-flops may be happier staying on the beach.
Kayaking and snorkelling
Many Ang Thong tours include kayaking along the cliffs or offer it as a paid extra, and for a lot of people it is the high point of the day. Snorkelling is usually on the schedule too. Expect modest visibility, though. The independent Thai National Parks guide notes that sediment from the Tapi River often limits how far you can see underwater.
What a Pig Island catamaran day looks like
The Samui Journey 1-Day Catamaran sails from Bang Kao Pier on Samui’s south coast and keeps the sea legs short, so more of the day goes on time in the water. This is the published schedule.
| Time | Stop |
|---|---|
| 9:00–9:40 AM | Hotel pickup (time depends on your area) and transfer to Bang Kao Pier |
| 10:30 AM | Set sail on a 4-engine fibreglass catamaran with a toilet on board |
| 11:20 AM | Five Islands (Koh Si Koh Ha): limestone rock formations and swiftlet nests, viewed from the boat |
| 11:50 AM | Koh Tan: snorkelling, paddleboard, kayak, floating sea pool, banana boat, springboard and water slide, plus Thai massage on board, all included |
| 12:45 PM | Lunch served on board |
| 2:50 PM | Koh Madsum (Pig Island) |
| ~4:30 PM | Back at your hotel (drop-off time depends on your area) |
The Five Islands hold valuable swiftlet nests that are guarded against poachers, so you look from the boat and don’t land. Most of the swimming happens at Koh Tan. Pig Island is a beach stop, where you meet the pigs and cool off in the shallows. Our Pig Island guide covers the island and how to behave around the animals.
Side by side: the differences that matter
Time ashore vs time on board
Ang Thong is a “go and see” day, and most of the reward is ashore, at the lake and the viewpoint. The catamaran is a “be on the water” day. The deck, the water slide, the floating sea pool and the swim stops are the point.
Effort and fitness
This is the biggest dividing line. Ang Thong rewards people who are willing to hike. On the catamaran you only have to get on and off the boat, and you can spend the whole day on a sunbed if you like.
Children and mixed groups
On the catamaran, under-5s go free and children 5–11 pay the child rate. Life jackets, a floating sea pool and shallow beach time mean kids and weaker swimmers can join in. At Ang Thong, younger children will like the boat, the kayaking and the beaches, but the viewpoint climb is too much for most of them.
Snorkelling
Neither trip is a dedicated reef-diving day. Of the two, Koh Tan is usually the easier snorkelling stop, with shallow water close to the boat and gear and life jackets supplied. If fish and coral matter most to you, read our guide to the best snorkelling spots around Koh Samui.
Food, drinks and comfort
Ang Thong lunches depend on the operator, and the boats range from big, slow ones to fast speedboats. On the Samui Journey catamaran, lunch is served on board, free-flow cocktails, mocktails and soft drinks are included, and there is a toilet and a Thai massage service on board, included in the price.
Seasickness
If you get seasick, two things help. Shorter crossings, and a steadier boat. The Pig Island route hops between nearby islands, and a large catamaran sits on two hulls, so it generally rolls less than a single-hull boat. Ang Thong means a longer open-water crossing each way, and speedboats in particular can feel bumpy when the sea is choppy.
Prefer an easy, all-in day on the water?
The Samui Journey 1-Day Catamaran includes hotel transfers, lunch, free-flow drinks, snorkel gear, water toys and accident insurance. Adults ฿3,300, children (5–11) ฿1,900, under-5s free. Check availability or message us on WhatsApp at +66 94 751 4988.
Which trip for which traveller?
| You are… | Better fit | Why |
|---|---|---|
| Keen hikers and landscape photographers | Ang Thong | The viewpoint over the archipelago is the payoff |
| Families with toddlers or young kids | Catamaran | No climbing, under-5s free, floating sea pool and life jackets |
| Mixed group with different fitness levels | Catamaran | Everyone can choose their own level of activity |
| Kayak lovers | Ang Thong (or both) | Paddling along the cliffs is the classic Ang Thong outing |
| Couples or friends after a social, relaxed day | Catamaran | Free-flow cocktails and mocktails, water toys, a floating sea pool, Thai massage and lunch on board |
| Visiting in early November to mid-December | Catamaran, weather permitting | Ang Thong is usually closed for its annual rest period |
Weighing up a speedboat tour or a private charter as well? Our overview of Koh Samui boat trips compared covers every option.
Can you do both?
Yes, on separate days, and many visitors do. A few tips if you plan both.
- Book the boat days early in your stay. If the weather forces a reschedule, you still have days to spare.
- Check the Ang Thong dates. The park usually closes from 1 November to 15 December for environmental recovery. The exact dates are announced each year.
- Keep a land plan ready. If the sea is too rough for any boat, spend a morning at Samui Elephant Kingdom (a three-hour ethical elephant visit) or do the full-day Explore the Real Samui 4×4 Island Safari instead.
To see which months usually have the calmest seas, check our month-by-month weather guide.
Good to know
- Ang Thong park fee: foreign visitors normally pay the national park entrance fee in cash on the day, unless your tour includes it. Fees change, so ask your operator.
- Sunscreen rules: Thailand bans sunscreens containing oxybenzone, octinoxate, 4-MBC or butylparaben in its marine national parks, with fines of up to ฿100,000. Pack a reef-safe sunscreen for any boat day and you won’t have a problem.
- Weather calls: Samui Journey checks sea conditions every day. If it is not safe to sail, we move your trip to another date free of charge. If that date is also affected, you get a full refund. Details are in the weather and refund policy.
- Minimum group size: the catamaran needs at least 40 guests to sail. If the number isn’t reached, you choose another date or a full refund.
- Cancellation: free up to 24 hours before pickup.
- What to pack: swimwear, towel, sandals, sunglasses, sunscreen and a camera cover most of it. Our boat day packing checklist has the full list.
Ready to book your Pig Island day?
Sail to the Five Islands, Koh Tan and Koh Madsum with a licensed captain (10+ years’ experience) and English- and Chinese-speaking guides. See the full itinerary or book online. Samui Journey Co., Ltd., TAT License No. 44/00252.
FAQ
Is Ang Thong better than Pig Island?
Neither is better. Choosing Ang Thong or Pig Island comes down to the day you want. Pick Ang Thong for dramatic scenery and hiking. Pick the Pig Island catamaran for an easy, social day of swimming and snorkelling that works for all ages.
Can you swim in the Emerald Lake at Ang Thong?
No. Swimming isn’t allowed in Thale Nai, the Emerald Lake on Koh Mae Ko. You look down on it from a platform at the top of a short, steep trail.
Is the Ang Thong viewpoint hard to climb?
It is steep and rocky, with rope-assisted sections, and the climb takes around 25–30 minutes. Fit adults in good shoes manage it fine. It is a poor fit for small children or anyone with mobility issues.
Is the Pig Island catamaran suitable for children?
Yes. Under-5s join free, there is no climbing, and life jackets and snorkel gear are supplied. The floating sea pool beside the boat gives younger swimmers a calmer place to splash about.
Is Ang Thong open all year?
No. The park usually closes from 1 November to 15 December each year for environmental recovery, and the authorities can also close it at short notice in bad weather.
Do you land on the Five Islands?
No. The swiftlet nests on Koh Si Koh Ha are valuable and guarded, so on the catamaran you see the rock formations and nests from the boat.
What happens if the sea is too rough on my booked day?
Your trip is moved, free of charge. The Samui Journey team contacts you in advance and rebooks you on another available date. If the new date is also affected by weather, you get a full refund.
Islands & boats
Islands & boats