Dedicate the third day of your trip to exploring the underwater world of Nga Bay. Go on a snorkeling or diving excursion to witness the vibrant coral reefs and diverse marine life. Swim alongside colorful tropical fish, spot sea turtles, and marvel at the beauty of the underwater ecosystem. If you're not a fan of diving, you can also opt for a glass-bottom boat tour to observe the marine life without getting wet. After a day of underwater adventures, indulge in a seafood feast at a beachfront restaurant.