Guanyan is a giant underground river cave located on the bank of the Li River. It is named after the mountain which resembles a purple crown. Visitors can not only explore on foot, but also enjoy sightseeing through various ways such as sightseeing elevators, rail trains, and wooden boats in underground rivers. There is a stalactite hall in the scenic area named Palm Hall. The reason for its name is that it has many large stalactite columns, shaped like large palm trees in the rainforest, and this hall is where the views are more concentrated and spectacular.