Beneath the US Capitol lies a vast underground fortress of tunnels, bunkers, and secret chambers that most Americans know nothing about. pplpod investigates this hidden infrastructure, exploring its original purposes, its evolution over time, and its current uses. From bomb shelters to secure passages to classified facilities, discover the physical underbelly of American governmental power and why governments build so much of their important work underground.

Key Topics Covered:

• Capitol Architecture: The design and construction of the Capitol's underground systems and how they integrate with the visible building above.
• Historical Development: How these facilities were built, expanded, and modernized across different eras of American history.
• Security and Protection: The role of underground infrastructure in protecting leaders during crises, attacks, or emergencies.
• Classified Functions: What can be revealed about how these spaces are currently used and what remains hidden from public knowledge.

Source credit: Research for this episode included Wikipedia articles accessed 3/5/2026. Wikipedia text is licensed under CC BY-SA 4.0; content here is summarized/adapted in original wording for commentary and educational use.