The underground city in the Gaza Strip was known to the army even before October 7. A force of an elite unit in the IDF with the fighters of the Shin Bet's operational unit advanced tens of meters underground in a narrow tunnel, 1.80 meters.

"When you enter a moral tunnel that is different from the others that everyone knows, you know that you are entering a combat zone with a chance of a firefight," says an officer who went down to one of Hamas' value tunnels. After long months of fighting, the commander of the Southern Command decided to delve into the mind of the senior member of the Hamas military wing, Muhammad Daf, and decided to walk the length of one of the long tunnels. He then brought to the security system an intelligence asset of dramatic value for understanding theMind of Hamas. The tunnels are connected and branching, some of which are close to the fence for an attack on the Israeli rear, some for the protection of operational assets, extended stay, storage of servers, weapons.