Mudouyu lighthouse is situated on Mudouyu Island, north of Baisha Township in Penghu County. Mudouyu is situated north of Jibeiyu, the most northern island of the Penghu Islands, and won its name because it is shaped like man's eye (mu means eye in Chinese); another story is that since this island was built by plateau basalt, and it is shaped like a carpenter's ink marker, it was originally called "Modouyu " (modou means the ink marker in Chinese), but because the pronunciation changed, it is not called "Mudouyu "; adding to the fact that it is situated at the north tip of the Penghu islands, it is also called the "North Island ".
Even during flood tide, the entire area of Mudouyu is only 0.0244km2, about the size of four basketball courts. This is an unmanned island, and despite being the large fishing ground north of Penghu islands, the water between here and Jibeiyu is only one meter deep, but it is an abrasion platform of submergence, fully surrounded by coral fringing reefs, shipwrecks are so common and constant here that it was once called the "Dangerous Penghu Bermuda Reef-striking Area ".
Mudouyu lighthouse is the first lighthouse established in Penghu after Taiwan fell under the Japanese colony. Since the island is narrow and long, in order to avoid the fierce wind and waves erode away the lighthouse, forcing it into early retirement, the lighthouse was built with a durable and lasting cast iron to begin with, and since it is situated in a foggy area, the exterior of the lighthouse was painted into black and white stripes as a loud warning sign, attracting attention of passing-by boats.
The Mudouyu lighthouse is 39.9m tall, the highest lighthouse in Taiwan, and the highest cast iron lighthouse built in the Far-east area (the lighthouse keeper is also the resident). The water access is inside the lighthouse, where the rainfall stored from the lighthouse and dorm rooftops is directed into the lighthouse, making this the only lighthouse that has a reservoir built inside the lighthouse. The island does not have electricity at the moment, and all electricity comes from the three generators to keep the lighthouse running.