Ang Thong Marine Park is an archipelago of 42 limestone islands two hours north of Koh Samui by boat. The Park operates as a protected national marine zone. Groups of 50-150 participants can charter vessels for a full-day program that combines guided activity with scheduled downtime on uninhabited beaches.
Planners use the Ang Thong day as an anchor activity in multi-day programs when the brief calls for a shared outdoor experience that delivers visuals, moderate physical challenge, and clear separation from resort environments. The islands have no commercial infrastructure. The Park authority restricts motorized activity in shallow zones and requires advance entry permits tied to specific vessel manifests.
The day runs long. Boats depart Samui's north shore marinas no later than 06:30 to reach the outer islands by 08:30, before wind builds. Return crossings leave the Park by 15:00, docking back at Samui around 17:00. Total program duration is 10-11 hours dock-to-dock.
Standard Day Program Structure
The typical Ang Thong itinerary breaks into three activity blocks with built-in rotation points. First stop is a snorkel site on the eastern edge of the Park, usually near Koh Wao or Koh Tai Phlao. Water depth averages 4-6 meters. Visibility ranges from 8 meters (good conditions) to 3 meters (post-rain or high plankton). Groups spend 45-60 minutes in the water. Guides brief surface protocols and buddy systems on deck before entry. Life jackets are mandatory under Park rules.
Second block is sea kayaking inside Emerald Lagoon (Talay Nai) on Koh Mae Ko. The lagoon sits in a collapsed caldera, accessible through a narrow channel. Tour operators shuttle groups in by longtail boat (the channel is too shallow for larger vessels), then distribute two-person kayaks on the interior beach. Paddle time is 45 minutes. The lagoon is landlocked saltwater, so there is no current. Water temperature runs 28-30°C year-round.
Third block is a beach stop on one of the uninhabited islands—typically Koh Sam Sao or Koh Phaluai. Crew set up a buffet lunch under temporary canopy. Groups have 90 minutes for swimming, photo sessions, or sitting in the shade. The beaches are coral sand with gradual entry. No facilities exist on these islands. Portable toilets are staged if group size requires it.
Activity sequence can flip depending on tide windows and Park traffic, but the three-block format holds. Total activity time is four hours. The remaining six hours are transit and transition.
Vessel Options and Capacity Trade-Offs
Two vessel categories handle groups at this scale. Traditional wooden boats (converted fishing platforms, often called "junks" in charter language) carry 80-120 passengers on open deck layouts. Modern catamarans carry 50-100 passengers with cabin seating and upper sun decks. The choice comes down to cost, aesthetic preference, and motion tolerance.
| Factor | Traditional Junk | Modern Catamaran |
|---|---|---|
| Capacity per vessel | 80-120 pax | 50-100 pax |
| Deck layout | Single open level, bench seating | Multi-level, cushioned seating inside and topside |
| Motion in chop | Rolls noticeably in 1m+ swell | Stable in moderate seas, softer ride |
| Speed | 12-14 knots | 16-20 knots |
| Aesthetic | High visual character, warm wood, traditional lines | Clean modern lines, Instagram-friendly |
| Cost | 30-40% lower per head | Premium pricing, smaller group minimum |
| Shade cover | Canvas canopy over 60% of deck | Full cabin plus shade nets on upper deck |
For groups above 100, you either charter two catamarans or one large junk. Chartering two vessels splits the group during transit but allows parallel activity rotation in the Park (one boat at snorkel, one at kayak). Single-vessel programs keep the group unified but extend dwell time at each stop while subgroups rotate through limited equipment.
Weather is the determining constraint. June through September the southwest monsoon produces afternoon wind and 1-2 meter swells in open water between Samui and the Park. Catamarans handle the crossing better. Traditional boats become uncomfortable in those conditions. October through May the gulf is typically calm, and both vessel types perform equivalently. If your program window falls in monsoon months, budget for catamaran pricing or plan a contingency land-based day.
Park Permits and Regulatory Requirements
Ang Thong is a national park under the Department of National Parks, Wildlife and Plant Conservation. Entry requires per-person fees paid in advance via the tour operator's permit allocation. Foreign nationals pay 300 baht per person. The fee includes Park entry and guided access to restricted zones like the lagoon.
Operators apply for group permits 7-14 days before the trip using passenger manifests. The Park releases daily quotas to control total visitor load. High season dates (December, January, Chinese New Year weeks) can hit quota, especially if multiple large groups file requests for the same day. Book the date at contract stage, not two weeks out.
Alcohol is prohibited inside Park boundaries. This includes on-vessel consumption once the boat enters the marine zone. Enforcement is inconsistent, but the rule exists in writing. Most incentive programs serve beer and wine during the return crossing after clearing the Park boundary. Communicate the restriction in pre-trip participant comms to avoid friction with guests who expect drinks at lunch.
The Park closes annually for ecosystem recovery, typically mid-May through mid-June. Exact dates shift year to year based on monsoon onset and Ministry scheduling. Confirm closure dates when scoping programs that touch those weeks.
Food and Beverage Layer
Lunch is served on the beach stop. Buffet format is standard: grilled protein (chicken satay, white fish, prawns), fried rice, noodle dish, fruit platter, bottled water. Tour operators prepare food at mainland commissaries and transport in coolers. Quality varies by operator. Halia works with a dedicated catering partner that stages hot boxes on the boat and finishes grills on portable burners at the beach. The difference shows in temperature and presentation.
Dietary accommodations require advance notice. Vegetarian and halal options are straightforward. Vegan, gluten-free, and allergy menus need 72-hour lead time and ingredient confirmation. Submit final meal counts and restrictions one week before departure.
Morning snacks (pastries, coffee, fruit) are typically served on the outbound crossing. Afternoon snacks (chips, cookies, soft drinks) on the return. Beer and wine service begins after Park exit. Confirm the beverage inclusion level when comparing operator quotes—some include two drinks per person, others run a cash bar, and premium programs offer open service.
Seasickness affects 5-10% of participants on a typical crossing. The outbound leg at 06:30 is smoother than the return at 15:00 (wind and chop build through the day). Stock seasickness tablets on the boat and mention them in the morning brief. Participants prone to motion sickness should dose 30 minutes before departure.
Why This Day Works for Incentive Groups
The Ang Thong program delivers three things planners prioritize for midsize incentive groups: a logistically contained experience (everyone moves together, clear start and end, no stragglers), a high visual payoff (the islands photograph well, the lagoon is distinct, beaches are clean), and a balanced activity intensity (snorkel and kayak engage the active participants, beach time accommodates the passive ones).
The day also creates natural conversation windows. Transit time on deck is unstructured social time. Lunch on an empty island pulls the group out of the resort bubble. The return crossing is when groups debrief the day, often with drinks in hand as the sun drops. These unscripted social intervals are harder to engineer in land-based programs.
Costs for a fully programmed Ang Thong day run 4,500-7,500 baht per person depending on vessel type, F&B tier, and group size. That rate includes boat charter, crew, fuel, Park fees, guides, snorkel and kayak equipment, meals, and insurance. Add 800-1,200 baht per person for premium catering or specialty beverage service.
Halia responds to program briefs and capacity requests within 48 hours. If your incentive scope includes an Ang Thong component, send group size, preferred dates, and dietary notes to /contact and we will return vessel options and a cost breakdown.
