The most obvious building on Mudouyu Island is the Mudouyu Lighthouse. It is 39.9 meters high and was built in 1899. At that time, to avoid corrosion and rust, it was made of cast iron and had black and white parallel stripes on the exterior as a conspicuous warning sign. It flashes once every 20 seconds, with a candlelight of 500,000 candles and an illumination range of 19 nautical miles.
The Mudouyu undersea tunnel is located at the north of Jibei Island and at the bottom of the cliff. Tourists usually snorkel near the sea fish here. When the tide recedes slightly and the tunnel entrance is exposed, they can enter the tunnel to enjoy the beautiful ocean scenery. There are organisms such as oysters on the rock wall, and there are coral reefs, fish schools and other scenery on the seabed. When the tide is high, pufferfish, tropical fish and so on can be seen. It is a very distinctive undersea scenery. However, for safety, it is recommended that tourists go when the tide is greatly receded around the 1st and 15th day of the lunar calendar. The tunnel is open all year round and all day.
