Ang Thong National Marine Park
Most of the islands are close to each other, making a breathtaking panorama when sailing around the park. All the islands are of different sizes and shapes. Most of them are covered with tropical forests and named after their distinguishing geography, a kind of descriptive appellation, such as 'Sleeping Cow Island' and 'Three Pillars Island'. Ko Wua Talap is the island that contains park headquarters as well as tourist information center, a restaurant,Buaboke Cave, tourist bungalows as well as the famous view point from where you can see the panoramic view of the National Park. Ko Wua Talap has two beaches. Both beaches are located on opposite ends of the island and it is possible to go from one to another via a short but by no means easy jungle trek (around 30 mins) using a trail. There is a rope all along the trail which ensures you do not get lost.
Ang Thong translates as "golden bowl". It occupies almost 250 sq km and includes 50 sq km of limestone islands and karst topography which rise from the sea as dramatic rock cliffs and bizarre rock formations. Caves, hidden lagoons, and white sand beaches are there to be explored and snorkelling among the shallow coral gardens makes for a popular and fascinating day trip.
Ang Thong National Marine Park is a protected nature area consisting of over 40 islands, and is famous for its natural beauty. All of the islands are uninhabited and undeveloped except for two. One being Ko Wua Talap and other, Ko Paluay, which is inhabited by sea gypsies who still earn a living from fishing.
Flora and fauna
The woods in this national park can be classified as dry evergreen forest, beach forest, and limestone forest. Dry evergreen forests are found in larger islands like Wuatalab, Paluay and Samsao.
Beach forests are lighter woods found in small stretches along the beaches and the shoulders. Limestone forests are found on limestone mountains with thin soil layer. Plants are smaller.
Larger animals do not thrive on these islands as they are small and dominated mostly by steep limestone mountains, with only few lightly to moderately slanted plains. Sixteen species of mammals like otters, langurs, crab-eating monkeys, hogs, silver haired bats, dolphins, and whales can be found here.
Other inhabitants include at least 54 species of birds, including little herons, Brahminy kites, common sandpipers, oriental pied hornbills, drongoes and hill mynas. Fourteen species of reptiles are also found. Such as ground lizards, iguanas, Green turtles, hawksbill turtles, pythons, and cobras.
Only five species of amphibians are found: common Asian toads, tiger frogs, rugose frogs, grass frogs, and tree frogs.
The waters of the national park are home to butterfly fish, angel fish, parrot fish, blue-spotted fantail rays, blacktip reef sharks, snappers, groupers, sea slugs, blue swimming crabs, sea fans, sea whips, giant clams, oysters, and coral. The park is also a breeding ground for mackerel.
Access to the park is controlled, but there are several Samui-based boat rental and kayak operators who are licensed carriers, catering to both independent visitors and organized kayaking day trips. There are also boats based on Ko Phangan or Ko Tao that run sailing livea board cruises to Ang Thong. For sailing livea boards from Ko Tao contact  or for budget group sailing cruises with accommodation ashore on Wua Talap Island in tents starting from Koh Tao or Koh Phangan, contact here or here 
You can go to the park via slow, time-consuming ferries with many other people in big groups (40-50 persons, only from Ko Samui or Pha Ngan) or in smaller groups (maximum 25 persons) by speedboat, so that you can enjoy more from park and less transit. As on Feb 2013 , Tours from Samui or Pha Ngan can cost anywhere between 1300 baht (including park fees excluding kayaking) to 2100 baht(Kayaking and park fee included).Tours includes pick-up from accommodation, a light breakfast, speedboat transfer to the park with nice snorkelling (better than anywhere on Ko Pha Ngan), visiting crowded touristy Emerald Lake viewpoint, then a buffet lunch either on the ferry or on Ko Wua Talap (park headquarters) island which contains the beautiful viewpoint. Reaching this view point on top of a cliff needs some tough hiking. If you can go to the top without breaks at three lower viewpoints and you are really fit you can be on top in 30 mins. Lower viewpoints with lesser views are less challenging.
Note that many times due to high tide on the main beach of Ko Wua Talap it is not possible for ferries to drop you on the main beach. In that case most operators will take you to the second beach on the other end of the island and will try to convince you stay on this beach robbing you of the chance to climb up to viewpoint. In that case do insist that you want to go to the other end using the jungle trail and that you need more time.
While most tourists will go on the day tour as per the itenary mentioned above , to truly appreciate the heaven that is this place it is recommended that you stay on the basic bungalows for atleast 1-2 nights. The reservation for the bungalows can be made by thai government website. Reservations should be made well in advance as they tend to get booked pretty fast.
If you want avoid crowds and money is not a problem or you are travelling with friends in a bigger group, you can do a private tour for 15,000 baht for a maximum of 10 persons.
Admission to the marine park is normally not included in the tour fee unless otherwise specified. 200 baht/foreigner, 100 baht for foreign children under 12 years old. Price for locals 40 baht.
The most common transport from Ko Samui are tour boats taking 40-50 people, with lunch on board. These require you to transfer to a longtail boat to get onto the shore of whatever island you are visiting, which can be tricky and requires a modicum of fitness.
You can take speedboat tours which also include a snorkelling program and fewer people. It gets you to the archipelago faster. The best way is to put together a group of friends to hire a boat and explore the islands and beaches on your own schedule.
Most tours go to the park's visitor centre for lunch and kayaking. The visitor centre is visited by most tour operators, making it very crowded, from about 10:00 to 16:00. Before and after, it's a totally secluded place with almost nobody around.
Ko Mae Ko (Mother Island) is a must-visit. Here, an emerald seawater lake in the middle of the island is encircled on all sides by limestone cliffs, but linked by an underground tunnel to the sea. Reaching the lake entails a strenuous climb of 40 minutes or so, but is rewarded with a spectacular view across the whole park.
The climb is up a series of staircases wonderfully combined into the natural landscape of the karst, threading through a narrow opening in the rock face at one point, and entailing minimum exertion if you pace yourself and are in decent physical shape. The final series of steps is a bit steep and caution should be exercised when descending the steps, but the entire trip up and down should not take more than 40 minutes unless you stop and enjoy spectacular Emerald Lagoon.
Caves on many of the islands have intriguing rock formations. Visit one for an awesome experience. The beaches are surrounded with excellent coral reefs which make for perfect swimming and snorkelling. Hundreds of beaches here in the archipelago are deserted. Get a boat and find your own secret beach away from the crowds.
Other popular sites are Ko Sam Sao (Tripod Island), with an extensive coral reef, and Wua Talap Island or "sleeping cow". It takes some effort to climb up the steep 430 m hill to a viewpoint offering great scenery of the entire archipelago and the mainland.
The main restaurant, managed by Nam, is excellent and offers a variety of cuisine. Be careful to order early as the cook leaves by 22:00 and the lights go out at 23:00. Cheapest meal is vegetable fried rice at 60 baht. Delicious meals with good portions cost 100-120 baht, worth every penny, but place your order as soon as possible, because preparation is VERY slow. Expect waiting for 30-40 minutes for meals in this uncrowded restaurant.
The park headquarters has two "bars" that sell beer. By "bar", we mean a cooler full of beer. But when sitting on the beach watching the sunset, it beats most bars and clubs fairly easily.
You should take water. You'll need plenty.
The park headquarters is located on Ko Wua Talap, which has basic bungalow accommodation.
The park has 5 bungalows which are of different sizes. The costs are quite low: 500 baht per day for a 2 bedroom cottage. The cottages are set against a beautiful backdrop and the park staff are very friendly, and fanatical about football. However, please note that the park is not for the resort seeker. Facilities are basic: no hot water. And the park shuts off its generator at 23:00. So no electricity at night (which only adds to the appeal of the place). Reservations can be made using thai government website [dnp.go.th/parkreserve/reservation.asp?lg=2].
If the cottages are full, you can rent a tent for 2 for 250 baht. You can also bring your own tent and camp at the campground. But you will almost always find a tent to rent.
Probably one of the best hikes in Thailand. At park headquarters there is a path leading up the side of the rocks. This will take maybe 25-30 minutes to walk up, and well worth it. But be warned, this is not a hike for the faint-hearted. Make sure you have good footwear as there are sharp limestone crags which will be your foothold, especially towards the peak. With a breathtaking view of all the Ang Thong islands, the end-result of the hike is well worth it. Beware though, the hike is very steep in some sections and offer questionable ropes to hang on to. But this hike alone will justify your trip to Ang Thong.
Obvious things like take water, hat, sunscreen and something like an old t-shirt to cover up with when you are snorkelling.