Ssangyong Cave is a representative lava cave in Jeju Island, along with Hwanggeumgul, Socheongul, and Manjanggul. The cave is approximately 400m long, 6m wide, and 3m high, and was created along with Hyeopjaegul Cave when a volcano in the Hallasan area erupted 2.5 million years ago. It is unique in that it is a two-dimensional cave that combines the characteristics of a lava cave and a limestone cave, and the area is made up of a sand and shell mixed layer. Inside the cave, stalagmites and stalactites, which are characteristic of limestone caves, are lined up like pillars here and there, creating a mysterious sight. The walls of the cave are covered with limestone, giving it a majestic appearance as if it were a huge mural engraved on it. The temperature inside the cave is maintained at 17-18℃ throughout the year, making it a unique summer resort in the middle of summer, and in the middle of winter, the cave is in the spotlight because the warm temperature allows you to avoid the cold. Ssangyong Cave is divided into left and right sides and was named Ssangyong Cave because it looks like two dragons were inside the cave and then escaped out. Since the second entrance of Ssangyong Cave and the end of Hyeopjaegul Cave are adjacent, it is presumed that the two caves were originally one but were divided due to an internal depression. Like Hyeopjaegul Cave, it is designated as a natural monument.