Hwanhaejangseong
Coastal fortification on Jeju Island built during the Sambyeolcho Rebellion.
Hwanhaejangseong (환해장성), sometimes called the Hwanhae Great Wall, is a coastal fortification that used to run along much of Jeju Island’s shoreline in what is now South Korea. It was first built in the 1270s during the Sambyeolcho Rebellion and stayed in use for many centuries. However, in the late 1900s, it suffered heavy damage, mostly from the construction of coastal roads on the island. In 1998, ten surviving sections, measuring a total of 5,120 meters, were made a Monument of Jeju Province.
The wall’s history begins in 1270, when the Goryeo government ordered a wall built on Jeju to stop Sambyeolcho rebels from seizing the island. But just two months after Goryeo forces arrived, the Sambyeolcho attacked and took control. It’s likely that the Sambyeolcho then continued building and extending the wall until their defeat in 1273. The wall remained useful afterward, especially for defending against Japanese pirates. In 1845, after a British ship spent about a month near the island, the walls were repaired—and possibly extended. What remains today is probably from that 1845 reconstruction.
The walls were made from local basalt, using traditional Jeju stone-building methods. But the wall’s shape and size varied along its length. Efforts to repair or rebuild it have been tricky because little is known about the original construction techniques.
According to historical records like the *Koryŏsa chŏryo* and *Sinjŭng Tongguk yŏji sŭngnam*, the first walls were built from Hwabuk (now part of Jeju City) east through Jocheon to Hamdeok. General Go Yeorim led the Goryeo defenders, who had previously fought the Sambyeolcho on Jindo. The *Sinjŭng Tongguk yŏji sŭngnam* says 1,000 soldiers were sent to build coastal defenses—called *gojangseong*—stretching 300 *li*. Other documents agree, though none give exact dates. Some of those 1,000 may have been up to 730 locals from Jeju, not all mainlanders. The *Goryeosa* mentions two groups sent: one of about 200 men, another of about 70.
Goryeo forces reached Jeju around mid-September 1270. Since the Sambyeolcho conquered the island in mid-November, it’s unlikely the Goryeo troops built the whole wall in just two months. Instead, the Sambyeolcho probably expanded whatever was started.
Quick Facts
- Length
- 5120 m
- Built
- 1270 onwards
Facts from the source article.
Lore & Background
The construction of Hwanhaejangseong began during the Sambyeolcho Rebellion. In 1270, Goryeo government forces were sent to Jeju to prevent its takeover by Sambyeolcho forces, and they built the first walls from Hwabuk east through Jocheon to Hamdeok. However, the Sambyeolcho attacked just two months after Goryeo forces arrived, taking the island. It is likely the Sambyeolcho continued to develop and extend the wall, before their eventual defeat in 1273. Historical records note that 1,000 soldiers were sent to construct coastal defences, though this number may include up to 730 native Jeju residents.
The wall remained in use during the Joseon period, seen as helpful in defence against Japanese pirates, who conducted over 30 invasions from the 13th to 16th centuries. In 1845, the walls were repaired and perhaps extended after the British HMS Samarang spent 40 days near the island. The current walls are likely a result of this 1845 reconstruction. The wall was mostly destroyed in the late 20th century, especially during construction of coastal roads in the 1970s and 1990s. Restoration efforts began in 2001.
Reader's Guide
Hwanhaejangseong represents a significant example of medieval Korean coastal defence, built during a period of internal rebellion and external threat. Its construction involved both Goryeo government forces and the Sambyeolcho rebels, with likely contributions from local Jeju craftsmen familiar with basalt construction. The wall's design varied along its length, incorporating local stone and traditional techniques similar to Jeju's batdam agricultural walls, though some sections featured a double-wall design with a higher seaward-facing wall. The wall's total length may have reached 120 kilometres, though only 5,120 metres of ten stretches remain today. Its designation as a Monument of Jeju Province in 1998 came after much of it had been destroyed by road construction. The wall's legacy is complicated by uncertainty about original construction techniques and the difficulty of distinguishing original sections from later repairs. It may have inspired the Genkō Bōrui in Kyushu, Japan, built after the Mongol invasions. Restoration efforts face challenges due to lack of knowledge about initial construction methods.
Did You Know?
- The wall was built using local basalt, and construction techniques likely varied due to differences in terrain.
- The Sambyeolcho forces likely extended the wall after conquering Jeju in November 1270, continuing construction until their defeat in 1273.
- In 1845, the walls were repaired after the British HMS Samarang surveyed near Udo for 40 days.
- The name 'Hwanhaejangseong' was first used in the 1918 Tamna Ginyun.
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