It’s the largest low-rise office building on Earth—and one of the most secretive. With more floor space than the Empire State Building and 17 miles of corridors, the Pentagon is the center of U.S. military command—but the public only sees a sliver of it. From forgotten tunnels to sealed war rooms, its true layout remains hidden even from most who work there.

In this episode, we uncover the forgotten history and classified secrets of the Pentagon: why it was built so fast, what lies in its deeper levels, and how its very structure was designed for control, movement, and defense. From the Pentagon Papers to lost access tunnels and internal surveillance, we reveal why this five-sided fortress is still one of the most off-limits places in America.