For the vast majority of Thailand's independent travellers, Thailand's Lower Gulf means the three idyllic tropical islands that make up the Samui archipelago, together with the 42 mainly uninhabited islands that constitute the wonderfully unique Ang Thong National Marine Park. Generations of backpackers have flocked to the tropical paradises of Ko Samui, Ko Tao and Ko Phangan. If you're seeking sun, gorgeous beaches, swimming, diving, and snorkelling and other watersports, or just lazy days in cheap beachfront cottages, then it's difficult to find anywhere on earth that is better suited for your needs. But these days, there is so much more to do and enjoy on these three heavenly islands: 24/7 partying; sipping refreshing cocktails while you enjoy incredible views of the shimmering gulf and fantastic sunsets; trekking and climbing across the islands' interiors; diving & snorkelling; cliff jumping; kayaking; stand up paddling; attending Yoga retreats…and much more. Ko Samui, the largest of the three islands, has become known for its five-star resorts and high-end spas, but there is still plenty of reasonably priced accommodation across the island, and visitors can party till dawn or find deserted beaches with the odd budget hostel to welcome you. The mystical island of Koh Phangan, famous for the hedonistic bucket-laden Full Moon Parties, has a treasure trove of places to explore - from the atmospheric temples to some delightful waterfalls and hiking trails leading to incredible viewpoints. It is also increasingly becoming a world-renowned centre for yoga retreats. The small volcanic island of Koh Tao is indisputably a world-famous diver's paradise, with over 18 established dive sites and around 40 diving centres and resorts to serve you and to get you PADI/SSI certified. With its shallow waters, the island is perfect for beginners, as well as for more experienced divers - not to mention the increasingly popular free diving fraternity. Then there are snorkelling and other water activities. If diving isn't your thing, Koh Tao has gorgeous beaches, beautiful sunsets, and 24/7 partying on the western coast. Or you can travel to the "get away from it all" beaches on the east and southern coasts. Challenging treks into the interior will be rewarded by fantastic viewpoints or isolated beaches. The unique Ang Thong Marine National Park is accessible from any of the three islands by boat. You can take a trip out there for a day's fishing or diving. Or you can explore, snorkel and kayak amongst its little islets, in the countless lagoons and caverns beneath the towering limestone cliffs. Probably the pièce de résistance is the beautiful inland 'Emerald' seawater lake, world-famous for a scene from the iconic film, "The Island".