Cheonghaejin Historic Site

The small island of Jangdo, just off Wando, was the base of Cheonghaejin, the maritime garrison founded by Jang Bogo, who dominated East Asian waters in the 9th century. A wooden bridge from Jangjwa-ri village takes you straight onto the island, where you can still trace ramparts, gates, a well and a line of wooden stakes in the tidal flats. It is not large, but it lets you walk around what was once the hub of trade between Silla, Tang China and Japan.

History: from anti-pirate base to trading hub

As a young man Jang Bogo went to Tang China and made his name as a soldier. Seeing Chinese pirates kidnapping Silla people and selling them as slaves, he returned home and asked the king for permission to build a base against them. In 828, King Heungdeok of Silla agreed and appointed him commander of Cheonghaejin.

Cheonghaejin stood where the Yellow Sea meets the South Sea, a point that ships sailing between Silla, China and Japan had to pass. With 10,000 men, Jang Bogo cleared out the pirates and took control of East Asian sea trade, gaining great wealth and influence. He was later drawn into a struggle over the Silla throne and was killed by Yeom Jang, an assassin sent by the court. Sources differ on the year, with 846 the most commonly cited. Cheonghaejin was abolished in 851 and its people were moved elsewhere.

A site rediscovered

For centuries the island was farmed and the remains lay buried. After Typhoon Sarah in 1959, a row of wooden posts appeared in the mudflats around the island and drew attention to the site. It was designated a Historic Site in 1984, and excavations from 1991 to 1996 shaped what you see today.

What to see

• Wooden palisade: Defensive posts driven into the mudflats near the entrance to the island. The line is about 331 m long, and radiocarbon dating placed it in the mid-9th century, confirming its link to Jang Bogo's time. It is easiest to see at low tide.
• Ramparts: An earthen wall about 890 m long runs around the island. One section has been cut open to show the rammed-earth layers.
• Outer and inner gates: The gateways between inside and outside, with a good view of the outer gate and the sea from the inner gate.
• Well and U-shaped structure: A well about 5.8 m deep survives along with the rammed-earth structure that protected it.
• Lookout platform (Godae): The high point of the southern wall, used to watch ships passing by, and the best viewpoint on the island.

Tripto tips

• Getting there: Walk across the wooden bridge, about 180 m long, from Jangjwa-ri in Wando-eup. At the lowest tides, twice a day, the seabed is said to be exposed enough to walk across.
• Combine with: The Jang Bogo Memorial Hall is on the village side of the bridge. Seeing its exhibition on his life and the role of Cheonghaejin first makes the remains much easier to read. The hall is closed on Mondays and on Seollal and Chuseok.
• Time needed: 30 minutes to an hour for a loop of the island, about two hours with the memorial hall.
• When to go: Time your visit for low tide to see the palisade. There is little shade, so bring a hat and water in summer.
• Fees: The island site is free to walk around. Check the memorial hall's fees and hours before you go.