Afghanistan
Afghanistan has an extensive series of historic tunnels used for transporting water, the kariz, and during the 1979–1989 Soviet war in Afghanistan, such tunnels were used by Mujahideen fighters. The Soviet 40th Army had their own tunnel rats, who were tasked with flushing people out of the tunnels, then going through the tunnels to disarm booby traps and kill those who remained. Meanwhile, the United States Marine Corps and the Royal Marines are involved in similar work during the current ongoing war in Afghanistan.
Read more about this topic: Tunnel Rat