Introduction to Nanding Island: Nanding Island is elliptical in shape, with an area of ​​700 square meters and a maximum altitude of 54 meters. It is entirely composed of majestic giant columnar jointed basalt. The stone pillars on the island are 20 to 50 meters high, and the pillars are from The top of the cliff plunges straight into the sea, resembling neatly arranged rows of daisies, and is called the "hair-like stone forest" of lava. The basalt was formed 45.8 million years ago. The columns are upright and closely embedded in each other. The cross-sections are mostly five-sided. The basalt columns hang high on the cliffs, as if they are hanging down, like the solidified glaciers of Antarctica.