The Vatican is embarking on a project to restore and digitize its archive of more than eight million photographic images.

The images, which date to the 1930s, comprise a unique visual history of seven pontificates.

But many of the negatives have been damaged by handling and poor storage, officials said.

The restoration project, unveiled at a news conference Dec. 7, will take at least five years.

The negatives — including early glass plate negatives — will be cleaned and scanned for digital preservation, and a new storage facility will control temperature and humidity levels to prevent future damage.

The archive had its beginnings in the 1930s, when Rome photographer Francesco Giordani set up a photo studio near the Vatican and was called to do various portraits of Pope Pius XI.

When Giordani retired in 1977, the photo archive was left with the Vatican, which didn’t really know what to do with the collection.