AP
A North Korean soldier glares at a South Korean guard at the DMZ.
The largest tunnel, which dumped out 30 miles from Seoul, could have transported a full division (30,000) of soldiers, along with weaponry, every hour.
By some estimates, North Korea has many more tunnels too — though none have been found for 23 years.
South Korean officials have said that while they take the threat seriously, they believe that North Korea has not been able to build any more secret tunnels into the South, according to the New York Times.
Some "civilian tunnel hunters" are not convinced, however, and spend their own time looking for vulnerabilities.
“I am doing this work so that we won’t have another war and nobody will be hurt,” Rev. Lee Jong-chang, a Roman Catholic priest and veteran tunnel hunter told the Times in 2012. "The invasion tunnels are North Korea’s last secret weapon.”
One has only to look at the discovered tunnels to tell that Pyongyang wasn't messing around.
Malcolm Moore of The Telegraph describes the "Third Tunnel Of Aggression":
It was carved out of the rock by North Korea, probably in order to launch a surprise attack on Seoul at the end of the 1970s. The mouth of the tunnel is under 30 miles from the capital, and emerges near the Freedom Motorway linking North and South.
According to the blurb on the sides of the tunnel, it was big enough for a full division (30,000) of soldiers, along with weaponry, to march through every hour.
The last tunnel found, discovered in 1990, was discovered in the eastern portion of the Korean DMZ. Writes Global Security:
This tunnel was buried 145 meters below ground and measured 2 meters high and 2 meters wide, large enough for three armed soldiers to run through side-by- side.
On March 9, 1990, North Korea, for the first time, admitted in a propaganda broadcast in the DMZ that they dug the fourth tunnel. They claimed that the purpose of this tunnel was to "facilitate peaceful reunification" by "replacing the concrete wall" that the north falsely alleges the South built.
Here's a photograph from the South Korean side of the Third Tunnel of Aggression. The South placed concrete blocks in the middle, and it's now become a tourist destination, but they don't allow photos any deeper inside.
