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Full Moon Party

Haad Rin aerial view

Archery (First Bow and Arrow Archery) (close to Chalok Lam on the road to Thong Sala). Four archers can have a go at the same time. People are very friendly (German spoken during high-season) and helpful.15 min for 150 baht.
Diving. Ko Pha-ngan has lovely sites around the island which are perfect for both beginners and trained divers. From easy dives off the beach to longer trips by boat you can experience the world of tropical diving. The waters around Ko Pha-ngan are much nicer than most people know: fine hard corals with a good range of reefs and tropical/pelagic fish. Sailrock, undoubtedly the most famous dive site in the Gulf of Thailand. Between Ko Pha-ngan and Ko Tao, all the wonders of this exciting site can be explored by all levels of divers. This spectacular rock rises out of the water creating the best wall dive with a maximum depth of 40 m. Providing a great range of marine life, spectacular underwater scenery, rock formations. There are several PADI dive-schools on the island, including: Haad Yao Divers a PADI 5 Star IDC Dive Resort on Haad Yao and Haad Chao Phao; Reefers Dive Resort on Haad Yao Beach; Sail Rock Divers; Lotus Dive Resort, both in Chalok Lam. You will, however, find many more dive schools throughout the island. Under Thai law, dive operators must be registered with the Tourism Authority of Thailand to improve quality of service, safety and help protect the customer from fraud. Check to make sure you are booking with a TAT registered dive centre.
Full Moon Party. If you're after party heaven you can't do better than Haad Rin, an expanded village of beach bars, cheap chicken burgers, and low cut figure-hugging outfits. It is most popular one night a month, the night of the Full Moon Party. Every bar is hopping, the beaches packed with trance, dance, buckets, and various other suspicious substances. However, if the sight of thousands of bottles and other trash repulses you, make sure you leave the beach area before the sun comes up, or grab a garbage bag and help tidy up a little. Haad Rin offers a variety of entertainment venues just steps away from the famous Full Moon Party beach, where travellers and locals come to get away from the repetitiveness of the beach party scene. Now the events are starting again after the COVID-19 situation. (updated Aug 2022)
Herbal Sauna (Near the 7-Eleven in Baan Thai, on the southwest side of the island.). Daily, 13:00-19:00. The herbal sauna at Wat Pho with separated men's/women's rooms is a great relief after long party nights. Always wear a sarong (over your bikini, for men it's OK to use shorts). Remember that you are on temple grounds and locals find nudity offensive. This is not a European sauna, sitting naked will get you into trouble. You can stay as long as you want.50 baht, towel 10 baht.
Hiking. Can be done all around the island. There is a trail that leads between Haad Rin and Haad Tien, which many enjoy. The route can become difficult to discern, and bringing enough water is necessary. If you are feeling adventurous, ride a motorbike to the end of the concrete road at Haad Khom from where you can hike through steep terrain and jungle on the coast to isolated Bottle Beach. The overgrown and difficult trail is occasionally marked with bottles and the hike takes 2–3 hours. Ride back to Chalok Lam with a taxi boat (150 baht/person) from where it's a 30-min walk uphill to the Haad Khom main road where you parked your motorbike (or you can hike all the way from Chalok Lam). Another good trail is to the best viewpoint on the island (in good weather), Khao Ra Viewpoint, on the highest hill on the island.
Muay Thai. Gyms such as Chinnarach offer training and workout facilities, as well as camps such as "Horizon" located in Haad Tien (east) which is an intensive training camp. There are also frequent bouts in Thong Sala and Haad Rin for spectators.
Watersports. Rent or take courses in sailing, windsurfing, kite-surfing or paddle boarding. All are available in only few locations such as, Sl2k Adventure at Baan Manali Resort in Ao Nai Wok or "Cookie Salad" at "Haad Salad".
Yoga. Offered at multiple places including Agama Yoga, which is in the northwest of the island and has month-long intensive courses.