Underground tunnel network

An underground tunnel network is a network of tunnels located underground.

During the 2014 Israel–Gaza conflict, the Israeli military uncovered and destroyed 32 cross-border tunnels that went on for miles beneath Gaza and reached into Israeli territory. According to intelligence officials, Israeli engineers are developing a system that could detect and destroy cross-border tunnels for which the Israeli government has reportedly spent more than $250 million since 2004.

A network of caves beneath the cities of Mosul and Badana were built by ISIS. The terrorist group avoids battlefield engagements, preferring to hide in such tunnels safe from satellite detection, drone strikes and artillery, managed to maintain supply lines and communication with other areas under their control.

The tunnels of Củ Chi are an immense network of connecting underground tunnels located in the Củ Chi District of Ho Chi Minh City (Saigon), Vietnam, and are part of a much larger network of tunnels that underlie much of the country. The Củ Chi tunnels were the location of several military campaigns during the Vietnam War, and were the Viet Cong's base of operations for the Tết Offensive in 1968.
The tunnels were used by Viet Cong soldiers as hiding spots during combat, as well as serving as communication and supply routes, hospitals, food and weapon caches and living quarters for numerous North Vietnamese fighters. The tunnel systems were of great importance to the Viet Cong in their resistance to American forces, and helped to counter the growing American military effort.

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