Melissani Cave is a stunning natural wonder located on the island of Kefalonia in Greece. This underground cave features a large, open chamber filled with crystal-clear blue water, which is fed by an underground lake. The cave is known for its unique geological formations and the sunlight that streams in through a large opening, creating a magical atmosphere. Visitors can explore the cave by taking a boat tour, which allows them to appreciate the beauty of the surrounding stalactites and the vibrant colors of the water. Melissani Cave is a popular destination for tourists seeking to experience the natural beauty of Kefalonia.