The Mandarin Ducks Grotto is a site of both geological and historical significance. The east-west valley landscape also makes it an excellent coastal fishing spot.
  
Due to the valley terrain, there are several shallow wells in the area. During World War II, the people of Wang'an dug multiple caves here to serve as air raid shelters. Over time, and as a result of natural forces, most of these shelters have collapsed.
  
The outer beach of the Mandarin Ducks Grotto is pure and tranquil, while offshore, the saddle-shaped Maanshan Islet stands as a natural barrier, situated approximately 600 meters away.
  
The "Bunker Cave" within the grotto is a remaining historical site. During World War II, the Japanese military requisitioned the residents of Wang'an and Jiangjun islands to dig the caves, which were used to store Shinyo motorboats and house special forces dormitories. The project was nearly completed when Japan declared unconditional surrender, leading to the abandonment of the site. Many of the caves have since collapsed, leaving only remnants.
  
Recommended Duration of Visit: 2 hours

Source: Penghu Travel