Ok, it's time for a friendly, honest Embark.org examination into one of Thailand's most popular visitors' attractions. While the 9-island archipelago that makes up the Mu Ko Similan National Park is indeed a beautiful retreat, there are probably some things you'll want to be aware of before making the journey 85 km northwest of Phuket Island. Of course there's lots of tropical island scenery to appreciate, with white sand, lush plant life and crystal clear water housing a variety of coral and marine life species. There are also hordes of tourists that flock here annually, most of them participating in roughly the same itinerary (think the obligatory climb up "sail boat rock"). This can make for a relatively disappointing day-trip, and some over-crowding at the best snorkel and dive sites.
The solution? Well, if you're going to come, why not make the most of it? Overnight stays help give visitors the opportunity to appreciate the beautiful surroundings without the congestion of day trippers, and Ko Similan (Island 8) offers tent and bungalow options at relatively inexpensive prices. Simple but adequate. There are also liveaboard dive boats that can be booked from Phuket, which avoid the most overcrowded areas altogether. All in all, the Similan Island experience can certainly be enjoyable, and you'll up those odds considerably provided you plan ahead and have an idea what to expect. Now go get 'em.