The Jeju Fortress () was a set of fortifications that turned the historical Jeju City into a . The only surviving major portion is officially referred to as Jejuseongji (). The site of Jeju City has been important to the administration of the island of Jeju since the time when the island was an independent kingdom named Tamna. It remained an important site when Tamna was absorbed into the Goryeo kingdom in 1105, and in all administrations since then. It is likely that there was some form of fortification in the Tamna or Goryeo periods, although written references are vague and no archeological remains have been found. The structure now generally referred to as the Jeju Fortress comes from the Joseon period, when walled towns were viewed as important for both defense and administration. It is unknown precisely when the Jeju Fortress was constructed, and whether it was built on a pre-existing structure, but a fortress of some for existed in 1408, and there are records of construction in 1411.
The fortifications constructed in 1411 were located between two streams: the Byeongmuncheon to the west and the to the east. The walls were likely constructed from local basalt. The coastline lay to their north, while the southern wall was built where the terrain began to slope upwards towards Hallasan Mountain. Gates were built into the eastern, southern, and western walls, with a road connecting the government complex and the eastern gate serving as the city's main thoroughfare. The walls were modified a number of times, most notably in 1565 when they were expanded east across the Sanjicheon. Two gates were later constructed where the Sanjicheon met the northern and southern walls. An inner wall was constructed along the western bank of the Sanjicheon in 1780 to help manage flooding.
The fortress was demolished after Korea came under Japanese rule in 1910. Different sections were demolished in different years, with the final destruction occurring in 1926, when material from the walls was used to expand the city's port. The former wall locations gradually became used for other purposes, such as roads. The area formerly encompassed by the walls slowly lost its distinct identity as Jeju City expanded southwards and government institutions moved to new locations.
The only remaining large section of the wall, part of the southern wall adjoining Ohyeondan Altar, was listed as a on August 26, 1971. Research into this site began in the 1990s, and by 2015 around had been restored. A small number of other surviving parts of the wall are known, the largest being only . Of the dol hareubang statues that once guarded the city's gates, 47 of the 48 have survived, although all have been relocated. The foundation stones of some removed in the 1960s remain in their original positions. References to the fortress have survived in placenames and street names, and some markers have been placed where the wall has disappeared.
History Earlier fortress The area that is now Jeju City has been an important administrative site since the time of the independent Tamna kingdom. This importance continued after Tamna was annexed by the Goryeo in 1105. It is thought that a fortress existed somewhere near what became the old city from either the Tamna or Goryeo periods, although there are no surviving written records of its exact location. It is unknown precisely what relation this earlier structure may have had to the Joseon construction. The Joseon fortress may have been a rebuilding or extension of this previous site, or an entirely new construction. Archeological finds from Jeju City evidence interaction with trade routes between Southern Song China and Japan, uncovering artifacts including a Wu Zhu coin.
The Joseon-era suggests that the Tamna kingdom had a fortress along the central northern coast. The Sinjŭng Tongguk yŏji sŭngnam and Jeungbo Tamnaji mention an older structure () as having existed during the Goryeo Dynasty. When these writings were made, the structure was already considered to be in ruins. This was recorded as lying to the northwest of the Joseon fortress. The placename "Mugeunseong" (), coming from (), exists today as a street name in the Samdo-2-dong district. This location corresponds to the placename "Jinseong" (), also meaning old fortress, which is also used in some historical maps. A historical marker was erected on Mugeunseong street by a local group in June 2009 to mark the location of the old fortress. However, no archeological evidence has been found of a large settlement on that site.
There is evidence of some possibly Tamna-era structures within what became the Joseon city. The Jejuhyanggyo Confucian School was built within what became the city in 1392. The 1432 (part of the Veritable Records of Sejong) records a stone fortress of 910 bo (paces, around ). This is about 1,000 cheok less than the length given in later records, and so may be a measure of the old fortress. There are two guardian statues that are located to the east and west of the Joseon fortress. Their origin is unknown, but they may date back to the Goryeo period.
Joseon construction Beginning in the late Goryeo period, the coastline of Korea saw frequent attacks from wokou pirates. The (post-Goryeo) Joseon kings saw constructing as a useful defensive measure against such attacks, as well as a measure to increase central authority. Coastal towns began to be extensively fortified under Sejong the Great, and walled towns became an important component of Joseon administration.
The exact date of the Joseon-era Jeju Fortress' construction is not known. A fortress is mentioned in records of a 1408 flood. The Veritable Records of Taejong records that the walls of the fortress were repaired and expanded in 1411. This 1411 structure was built between two streams: the Byeongmuncheon to the west and the to the east. The location lay at the edge of the coastal plain, with terrain rising from its south towards Hallasan mountain. During high tides, shipping could reach the sea through the Sanjicheon. The city was laid out along an east-west axis, with the focal point being a plaza (where was constructed in 1448). The main thoroughfare ran from this plaza towards the east. The road from the plaza to the west gate was likely not for public use. Like many structures in Jeju, the Jeju Fortress was constructed from basalt, which is common throughout the island. Material was thus likely quarried locally. Basalt is relatively resistant to water damage, which helped preservation.
Walled towns were traditionally located against mountains, in locations with easy access to drinking water and agricultural land; a system influenced by ancient Chinese urban planning. The Jeju Fortress was normal in these respects. However, the positioning of Hallasan to the south and the coast to the north was unusual feng shui. This positioning was likely due to the ancient importance of Hallasan to the location (as well as to other areas of Jeju island). Government buildings faced south, towards Hallasan, while Gwandeokjeong faced east. In most walled towns, the road from the southern gate to the was the main thoroughfare, rather than the road to the eastern gate. In Jeju, the east road was about wide, whereas the south road was only wide. The east road connected the government buildings, including the gaeksa, to the northern river exit that led to the city's port. The road further extended to the port towns of and Jocheon.
A new administrative system was put in place in 1416, under which the Jeju Fortress was responsible for administration of the whole island. The fortress was the first completed part of the new Joseon defensive system. It served directly as the capital of the Jeju-mok administrative area. The rest of the island was covered by the two hyeon (counties) of and . A walled fortress was soon built in each to serve as an administrative center. Aside from these 3 fortresses, the island-wide defensive system included 9 military camps, 25 beacon stations (bongsu), and 38 coastal watchtowers (). These were positioned to protect the island from invasion. The full system of defences was completed by 1678. Official inspections of the island began at the Jeju Fortress' east gate, and circled the coast before ending at the west gate.
The three walled towns remained the core of the island's administration throughout the Joseon Dynasty. Each had a Hyanggyo school, as well as other government facilities. The governor of the Jeju Fortress, who had both administrative and military roles, held seniority over the leaders of the other two walled towns. The importance of the Jeju Fortress was reflected in its name. The earliest known records call it jejuseong (). When the use of walled towns () spread throughout Joseon, the fortress gained its current name of jejueupseong (). However, in some later documents it was named jejudoseong (). Doseong () was generally used to refer to capital cities, so the name likely reflected a continued cultural association of Jeju City as the capital of a once-independent Tamna.
Later expansion
There are written historical records documenting later repairs and modifications to the fortress. The original fortress was likely only long with only three gates: eastern, southern, and western. (The lack of a northern gate was probably a defensive measure, due to the nearby coastline.) The east gate was referred to as yeonsangru (), the south gate as jeongwonru (), and the west gate as jinseoru ().
The 1481 Sinjŭng Tongguk yŏji sŭngnam records the town walls having a circumference of 4,394 cheok (about ) and a height of 11 cheok (about ). Adding to the natural defences provided by the two streams, a moat was dug around the walls and drawbridges were constructed in 1512. The wall at this time was 5,486 cheok long. The moat may have been filled with thorny trees rather than water. The addition of a moat was unusual for Korean walled cities.
Wokou besieged the fortress in 1555, but were unable to breach the walls. Following this, the fortress was extended east over the Sanjicheon in 1565. This brought drinking water into the city walls, and encompassed an eastern hill that previously overlooked the fortress and had been used by the wokou. The walls were also raised 5 cheok.
The walls were expanded again in 1599 to strengthen defences following the end of the Imjin War, reaching 6,120 cheok. The wall was widened to 5 cheok, and its height was increased to 13 cheok. Two river gates were built at this time where the Sanjicheon flowed through the northern and southern walls. The northern gate allowed boats to enter the city. It did not have strong defensive structures, likely due to the river gates being vulnerable to flooding. 1599 also saw the construction of new gate towers and other pavilions, including the Jeigak pavilion () above the southern river gate. 21 of the 27 bastions were converted to use cannons. A watchtower named jukseoru () was placed above the bridge at the northern gate. The 1599 constructions took place during the winter, and resulted in many deaths, giving the fortress the nickname wonchugseong (). The initial three gates and the two river gates would persist throughout later modifications.