During the Cold War, this underground bunker in Culpeper, Virginia was where the government would have taken the president if a nuclear war broke out. Now, the Library of Congress is using it to preserve all manner of films, from Casablanca to Harry Potter. The oldest films were made on nitrate, a fragile and highly combustible film base that shares the same chemical compound as gunpowder. Great Big Story takes us inside the vault, and introduces us to archivist George Willeman, the man in charge of restoring and preserving the earliest (and most incendiary) motion pictures.

For more on the Library of Congress' efforts to preserve American film history, see this Wired article.