Popularised by its role as home to a utopian beach society in the movie version of Alex Garland's novel The Beach , Ang Thong National Marine Park is made up of an archipelago of about 40 small islands combining sheer limestone cliffs, hidden lagoons, white-sand beaches and dense vegetation providing a postcard-perfect vista almost anywhere you look.
The numerous caves and crevices are home to nesting swallows and there's a narrow coral reef in the southwest of the park.
From Ko Samui, a couple of tour operators run day trips to the Ang Thong archipelago from Na Thon or Mae Nam.
There are bungalows available at the park headquarters on Ko Wat Ta Lap, but you may not be able to reserve them unless you go with a tour.