Tunnels in Incheon's Bupyeong reveal imperial history

Inside Tunnel 6 in Area C of eastern Incheon's Bupyeong District. Sept. 8. Courtesy of Jack Greenberg

By Jack Greenberg

It was a Friday evening, and the sun was beginning to set. I got off the bus near the gates of the Central Force for National Defense's 3rd Supply Depot and walked along its barbwire perimeter. Against the concrete fence, senior citizens were getting ready to turn in for the day after tending to the narrow vegetable gardens they had planted there.

Just before Inpyeong Automotive High School, I rounded the corner and began climbing a narrow path lined with mounds of empty detergent bottles, scraps of metal and other junkyard waste. Eventually, I reached my destination ― a small gravel lot at the foot of Mount Hambong. A few folks were already gathered and waiting for others to arrive; a couple of schoolchildren tested their flashlights and headlamps excitedly while the adults passed around a bottle of mosquito spray.

The Bupyeong Cultural Center organized a special nighttime excursion to educate members of the community about a neglected aspect of forced labor under Japan's colonial occupation, as well as to commemorate the 78th anniversary of Korea's liberation.

People go on a tour at night of tunnels in eastern Incheon's Bupyeong District, Sept. 8. Courtesy of Jack Greenberg

Incheon's eastern Bupyeong District has long been synonymous with Camp Market, a now-shuttered U.S. Forces Korea (USFK) installation. However, the American presence in this area was preceded by the Japanese, who established a training base here for the 20th division of the Imperial Japanese Army as well as an armory and weapons manufacturing facility. Its construction began in the second half of 1939 and was completed by December 1940. Officially, full operations kicked off in May 1941. The armory was one of seven in the Japanese Empire, and the first to be established in any of its colonies. The manufacturing facility specialized in producing, repairing and storing rifles and guns in addition to sword bayonets, ammunition and grenades. Apart from weaponry, it produced parts for military vehicles, aircraft and submarines.

Our destination that evening was one of the tunnels that had been dug at the orders of the military authorities as Japan's defeat loomed at the end of the Asia-Pacific War. In 1945, the Japanese were not ready to stop fighting even as bombs rained down on mainland Japan and military defeat revealed itself as a foregone conclusion. Accordingly, plans were made to hide the facilities of the Incheon arsenal underground as preparations were undertaken for a decisive battle on land. The colonial authorities feared that the arsenal's weapons-making activities would make it a prime target in the event the U.S. initiated an aerial bombardment campaign over the Korean peninsula. Tunnels with a similar appearance and size to those in Bupyeong have also been unearthed in areas near the Osaka Army Arsenal.

Locals of a certain age were aware that the tunnels at Mount Hambong dated to the colonial period but knew them only as a place ideal for fermenting salted shrimp harvested from local ports because of their cool temperature. Nevertheless, oral testimony was collected regarding the forcible mobilization of young Koreans ― some no older than middle school age ― for their construction.

To establish the truth regarding the tunnels, Bupyeong Cultural Center has been collaborating with local researchers and historians since 2016 to collect written evidence regarding the tunnels' purpose. Obtained records highlight that underground facilities were intended to measure a floor space of 15,112 square meters in total.

Moreover, 15,000 Koreans ― divided between general workers and conscripts ― were to be mobilized for the construction of underground facilities as well as supporting infrastructure such as roads, sewage systems, rails and dormitories. This figure would have been on top of those already working in the existing arsenal. Although never realized, a proposition was also laid out to reassign the capacity of the Tokyo arsenal to Incheon after the former sustained significant damage in firebombing air raids.

Entrance to Tunnel 1 is on private property near the foot of Mount Hambong in eastern Incheon's Bupyeong District. Sept. 11. Courtesy of Jack Greenberg

Twenty-seven tunnels have been discovered so far. Seven were uncovered in Sangok-dong, four of which were destroyed in 2019 during construction. Another four were confirmed through satellite imagery near Cheongwon Kindergarten yet residents have blocked off their entrances as a safety precaution. Nine, of which several have been finished with concrete, are located inside an active military base, and are thus inaccessible to the public. This leaves seven in Area C, which were used for the fermentation of salted shrimp. Tunnel C-6 has been the target of intense survey and excavation work and is thus being promoted as an educational asset.

After donning white safety helmets outside, our group ventured into the cold and wet space with a muddy floor. The length of the tunnel was roughly 160 meters, and it was easy to stand upright without needing to hunch over. Making our way through the dimly lit passage, we stopped to see clusters of small limestone stalactites and a Japanese-style wooden wedge stuck in the ceiling above. At the endpoint, holes were visible in the rock surface, suggesting that the tunnel was meant to extend deeper into the mountain. Mobilized youth would have been assigned to break these holes using chisels and then clean out the rubble, following which a Japanese soldier would lay dynamite to blast through it. The young laborers would have then been required to haul away the debris.

At this point, we dimmed our lamps for a moment of silence to remember the hardships and suffering of the young people who toiled in the dark. Standing in this place makes you emotionally involved with this painful history and reminds you that it should not remain forgotten even as the state forges ahead with its goal of a future-oriented relationship with Japan.

In response to increased interest and to continue spreading awareness about this history, the Bupyeong Cultural Center has been offering tours in September, conducted only in Korean. There is no fee to participate, but prior registration on the Bupyeong Cultural Center's website at portal.icbp.go.kr/bpcc is required since each tour is limited to 15 people. It is anticipated that tour programs will be expanded further in the fall. For those unable to join in-person, a 360-degree panoramic VR experience is available on the website too.

Jack Greenberg is a recipient of the Global Korea Scholarship, currently pursuing a master's degree at Korea University's Graduate School of International Studies. He is interested in the history of South Korean housing and urban development and documents the changing cityscapes across the country in his free time. Follow him on Twitter at @jackwgreenberg.