| Abstract: |
Hundreds feet underneath the earth surface， there is an invisible strenth. It is a super structure strong enough to resist nuclear explosion and powerful enough to see the outer space two million and three thousand miles away. With the help of 1.5 million pounds detonator, hard granite which could hold two million and three thousand trucks was exploded to made this unparalleled underground fortress, hiding in the center of the rock mountains. Its high tech sentinels keep the USA from dissolving strike. This mysterious world is North American Air Defense Command. |
