The rugged beauty of Mother Nature is on full display in Angthong National Marine Park, an archipelago of 42 islands. Here, you'll find a world of steep limestone cliffs, secluded beaches, sparkling lagoons and fish in colors that rival a box of crayons. A speed boat will take you from Nathorn Port, where you will come ashore (off the tender boat) from the ship. Then, your captain will steer a course northwest of Ko Samui for a chance to dip in the sea and explore coral reefs and the underwater world of parrot fish and sea turtles. Later, you'll head to Ko Mae Ko Island for a hike to the island's main attraction-Emerald Lake, also known as Blue Lagoon, which is surrounded by a tropical rainforest and limestone cliffs with never-ending views. Finally, you'll cruise to Paluai Island for an Asian-style Thai lunch before returning to port.