Elberton, Georgia (CNN) -- In the beginning, there was the stone.
The blue-gray vein of granite that courses through northeastern Georgia spawned jobs in the quarries and finishing sheds of Elberton, where generations of stonecutters have turned slabs of rock the size of refrigerators into statues, tombstones and tile.
And one day, it brought a visitor who gifted the town with a landmark that leaves visitors scratching their heads decades later.
The nearly 20-foot high series of granite slabs known as the Georgia Guidestones are inscribed with a series of admonitions for a future "Age of Reason." Billed as "America's Stonehenge," it's an astronomically complex, 120-ton relic of Cold War fears, built to instruct survivors of an Armageddon that the mystery man feared was all too near.