Ko Samui is an excellent choice for families travelling with kids as there are many activities especially geared to the little ones, but there's also a lot on for teenagers too.
Be wary of 'Ecotourism' tours on the island – many are just commercial operations with little concern for what they may appear to promote and can involve treatment of animals that is detrimental to them.
If you’re serious about diving, head to Ko Tao and base yourself there. If you’re short on time and don’t want to leave Samui, there are plenty of operators who will take you to the same dive sites (at a greater fee, of course). Try to book with a company that has its own boat (or leases a boat) – it’s slightly more expensive, but you’ll be glad you did it. Companies without boats often shuttle divers on the passenger catamaran to Ko Tao, where you board a second boat to reach your dive site. These trips are arduous, meal-less and rather impersonal.
Certification courses tend to be twice as expensive on Ko Samui as they are on Ko Tao, due largely to use of extra petrol, since Ko Tao is significantly closer to the preferred diving locations. You’ll spend between 14,000B and 22,000B on an Open Water certification, and figure on between 4500B and 6200B for a diving day trip including two dives, depending on the location of the site.
Ko Samui’s hyperbaric chamber is at Big Buddha Beach (Hat Bang Rak).
One excellent way to to see an entirely different aspect of Ko Samui – and one that does not get enough mileage from visitors – is hiking the interior. There are several excellent viewpoint hikes, including the Mae Nam Viewpoint Trek, which take you into the jungle and up to serene vistas over the island. Many of these treks can be done on scooter or bicycle too, or a mix of cycling and walking.
Tired of tours and busy beaches? For the intrepid DIY traveller there's no better way to spend a day on Ko Samui than with a trip to the white sands of Ko Tan. Hire a long-tail boat from the boatmen who beach their boats alongside the strip of seafood restaurants on Hat Thong Tanot on Ko Samui's south coast; a boat for up to six people should cost 1500B to 2000B for a four-hour trip. The island itself is only about 15 minutes from Ko Samui. While the snorkelling isn't that great, the white-sand beach is empty aside from the occasional visit by charter boats and local fishermen, and the views and swimming are sublime.
Spas & Yoga
Competition between Samui’s five-star accommodation is fierce, meaning spas are of the highest calibre. For top-notch pampering, try the spa at Anantara in Bo Phut, the Hideaway Spa at the Six Senses Samui or the spa at the Banyan Tree Koh Samui. The Spa Resort in Lamai is the island’s original health destination, and is still known for its effective ‘clean me out’ fasting regime.
Yoga is offered at many hotels and is also big business. Ko Pha-Ngan is perhaps more the place for the hard-core, but you won't have a problem finding classes on Ko Samui – try Samahita Retreat or Absolute Sanctuary.