From the Korea Times:
Andrei Lankov
9/3/2006
In days gone by, underground mining was an important military activity, an essential part of any protracted siege campaign. Military miners, known as sappers, were discreetly digging tunnels under the walls and towers of the enemy castle, in the hope of collapsing them or, in later eras, stuffing the tunnels with explosives and blowing up the walls. The defenders were digging their own tunnels, trying to intercept the attackers and prevent them from completing their works.
Some digging operations took place during fairly recent campaigns, including even the First World War, but by and large sappers have been disappearing for the past few centuries– to be reborn in popularity, of all places, in North Korea during the 1970s.
The late 1960s was when the Pyongyang generals were serious about invading the South. I do not have proof (nobody has), but it feels that until the mid-1960s the North did not view an attack of the South as practical. The same was the situation from the mid-70s onwards. But between 1965 and 1975, the North Korean generals were probably really thinking about starting a Korean War once again.
However, the North Korean generals had to deal with one serious problem: they would have to breach the heavily fortified positions of the enemy who was likely to enjoy considerable air superiority. Hence, somebody came up with a brilliant idea: since we cannot drop our paratroopers behind the Southerners’ line, we can let our soldiers pass beneath the enemy’s position! We do not know whose idea it was – but I think that in due time the person’s name will be known to every student of Korean military history.
Thus, at some point in the late 1960s, the idea of an infiltration tunnel was born. It is believed that the large-scale construction began in 1971 when Kim Il Sung signed a special order authorizing the unusual plan. He is quoted as saying: “one tunnel can be more powerful then ten atomic bombs put together, and the tunnels are the most ideal means of penetrating the South’s fortified front line.”
According to published materials from US/ROK intelligence, each North Korean battle-line division, stationed near the DMZ was ordered to build two infiltration tunnels. As there were 11 divisions along the DMZ in the 1970s and 1980s, there should be 22 tunnels – if the intelligence is correct, that is. Only 4 tunnels have been discovered so far.
Strange noises and frequent explosions began to be heard in some parts of the DMZ from late 1973. Seismic monitoring equipment confirmed that some underground works featuring the heavy use of explosives were taking place. Finally, a North Korean engineer defected and provided information on the approximate locations of two tunnels. This led to intensive searches and, eventually, to the discovery of these impressive underground structures.
The first tunnel was discovered in November 1974, in the western part of the DMZ, some 60 km from Seoul. With an estimated total length of 3.5 kilometers, it extends one kilometer into the southern territory of the Military Demarcation Line that divides the DMZ. The tunnel is 1.2 meters high and 0.9-1.1 meters wide. This is not very large, but it still means that an entire regiment can pass through it every hour.
The next few years was a time of intensive counter-mining operations, as they used to be called in medieval times. Many methods were used to locate the tunnels, but good old ‘counter-mining’ proved to be most useful. First, bore holes were drilled in suspicious areas. Once discovered, a North Korean tunnel was counter-mined by digging an interception tunnel.
The second tunnel was discovered in March 1975. This tunnel was the most remarkable of all known structures of this kind. It is located in the central sector of the DMZ, about 13 kilometers away from Chorwon city, and about 100 km to the north-east of Seoul. The second tunnel is much larger (2.1-2.2 meters wide, 2.0 meters high), and it is the only known tunnel which would allow for the movement of armored vehicles and field artillery. An entire division can pass through it every hour. To facilitate the troop movement, a spacious troop assembly area was carved out inside the tunnel which has three exits.
The third tunnel discovered was slightly smaller, but it was also the closest to Seoul – and located merely 4 km from the truce village of Panmunjom. The tunnel was discovered thanks to a tip from a North Korean defector who had taken part in its construction. After its discovery in October 1978 for two decades no new underground structures were located, and for a while the tunnels appeared to be a thing of the past.
But a fourth tunnel was discovered in 1990, showing that tunnel building had continued into recent times. The US/ROK military insist that there are 18 undiscovered tunnels, probably now completed, along the DMZ.
There are some people who believe that some of these undiscovered tunnels have penetrated much deeper into the South, almost reaching Seoul. They even conduct searches for these tunnels, using private donations and the efforts of volunteers. Well, what should I say? Their pet idea does not appear very likely, of course, but there are always people who want to believe in something improbable. The story of the search for tigers in the DMZ is yet another confirmation of this.
