The Archivio Apostolico Vaticano — the Vatican Apostolic Archive — is one of the largest single institutional archives in the world. In 2019 Pope Francis officially renamed it from the “Vatican Secret Archive” (Archivio Segreto Vaticano) to the Apostolic Archive. The word “secret” in the original name meant “private” in its historical Latin usage — belonging to the Pope personally rather than open to the public — but its modern connotations created persistent misunderstanding. The renaming was a clarification, not a policy change. The archive has been open to credentialed researchers since 1881.
What the Archive Holds
The Vatican Apostolic Archive holds over 600 archival fonds. The holdings include: the complete diplomatic correspondence of the papal curia and its nunziature (embassies) covering 75+ nunciatures from the 16th through 20th centuries; records of the major offices of the Roman Curia; the complete proceedings of Vatican Council I (1869–1870) and Vatican Council II (1962–1965); archives of Catholic noble families who deposited their records with the Holy See; records of the Pontifical Commission for Sacred Archaeology; and the complete trial record of Galileo Galilei.
The Galileo Trial Documents
The most historically significant holding for scientific history is the complete documentation of the Galileo affair: his correspondence with the Church, the inquisition proceedings, his abjuration, and the subsequent handling of his case over centuries. These documents record the moment at which the Church officially suppressed heliocentric cosmology — the same institutional posture that is now relevant to discussions of how institutions manage paradigm-disrupting observations.
Physical Access
The archive is open to credentialed researchers at Città del Vaticano. Current hours (from September 15 reopening): Monday–Tuesday 08:00–16:15; Wednesday–Friday 08:00–12:45. Access requires an advance admission request. Photographic reproduction of documents is available for a fee. The admission request form is at archivioapostolicovaticano.va/content/aav/en/consultazione/admission-request.html. Academic credentials are required; independent researchers must demonstrate scholarly purpose.
Source: archivioapostolicovaticano.va. Archivio Apostolico Vaticano. Access and consultation section. Renaming announced February 2019.