The photograph above shows the entrances to one of the largest underground complexes on earth, one carved out of the solid rock of the Wasatch Range at the mouth of Cottonwood Canyon some twenty miles east of Salt Lake City. Its access tunnels are sealed by steel doors weighing nine tons each and further protected by iron gates; uniformed guards make their rounds and a closed-circuit television system monitors all movement inside. Emergency generators lie in readiness should the occasion arise, and a reserve water system containing thirty-six thousand gallons can be tapped for the use of the eighty workers who man the files and catalogues and computers that fill the tunnels and cavernous rooms. Overhead, more than seven hundred feet of granite provides a shield against natural or man-made catastrophe.

It is not a back-up facility of the Defense Department’s huge NORAD bunker somewhere in the Midwest, nor is it a secret CIA operation; it is the Granite Mountain Genealogical Vault, constructed by the Church of Jesus Christ of Latter-day Saints in 1965 at a cost of more than two million dollars. It is the largest genealogical library anywhere in the world. Its more than 980,000 catalogued rolls of microfilm—each the equivalent of three hundred printed pages—contain and preserve millions of entries from family trees whose branches extend throughout much of the civilized world—to the United States, England, Scotland, Wales, Canada, Mexico, France, Germany, Hungary, Denmark, Sweden, Norway, Fiji, Panama, Australia, and New Zealand. In addition, tape-recorded oral genealogies are on file from Tonga, New Zealand, the Cook Islands, the Society Islands, the Austral Islands, and even China, where oral records have been traced back to A.D. 900. Every month, another four thousand microfilm rolls are added to the collection.

The purpose? In Mormon theology, family ties are not generational, but eternal; ideally, all ancestors belong in heaven with their descendants, but this can only be realized if the descendants bond their ancestors to the church in a “sealing” ceremony, a kind of second baptism—and this can only be done if the name of the ancestor is known. And so the search goes on, the names pursued with the profound tenacity that has marked the church from its beginning. Superficial logic would suggest that if the search goes on long enough, the name of nearly every human being who has lived on the earth within trackable time ultimately will find its way into the files of Granite Mountain. This seems unlikely.