Seonyudo Island, one of the most popular tourist destinations on the west coast during the summer, lies in the heart of the Gogunsan Archipelago. The island has an area of 2.12 ㎢, which is only about 1/4 of Yeouido in Seoul. The island's coastal shore is around 12.8 kilometers long and the highest point is Namaksan Mountain, which reaches about 155.6 meters in altitude. Seonyudo is the central point of Gogunsan Archipelago and has even served as the headquarters for the naval army during the Joseon dynasty. It played a vital role during the Imjin War as Admiral Yi spent days in the islands to prepare for the next battle after his victory in the Battle of Myeongnyang. 

Visitors can enjoy the island in three ways. First is to look around the neighboring islands. Seonyudo, Munyeodo, Jangjado, and Daejangdo islands are all connected by a bridge, allowing one to move between the islands on foot or on a bicycle. Other ways to enjoy the island is to take a walk along the Myeongsa-simni Shore, one of the Eight Scenes of Seonyudo, and to try the clam collecting program at a mudflat.