Ang Thong National Marine Park is a must-see place to visit Samui. It consists of several small islands with a beautiful scenery. It is recommended to arrange an entire day here. In addition to snorkeling, we also climbed the mountain at Koh Mae Ko to see the Yamanaka Lake. It was pretty, and the slope along the path was slightly steep. Later, I also took a kayak. Even if two people are together, it is a bit of physical exertion.