SOURCES

Every source behind the map, the stories and the registry — the ones we used, the ones we checked and set aside, and the leads not yet read, each with the reason. Where a work is under copyright you see only the passage we relied on and a link to the rest; public-domain books open in full in the Reading Room.

1 OF 531 SOURCES

• JOURNAL

  LEAD — NOT YET READ

  The Los Tayos Expedition

  John Frankland · Caving International no. 1 · 1978

  The expedition's own account. Not read.

  MAP · CUEVA DE LOS TAYOS — THE METAL LIBRARY THAT NEVER WAS