In "By the Waters of Babylon", how long has it been since the people in the dead places were alive?
In "By the Waters of Babylon" it is unknown how long it has been since the people in the dead places were alive, but you can reasonably conclude that many generations have passed in the time since. John states that traveling to the dead places has been “forbidden since the beginning of time” and also references studying the “old books” and learning “how to make the old writings”. John describes the roads to the dead places as “falling apart into great blocks of stone” and also mentions that the bridges are not passable as they are “broken and fallen like broken vines”. Many of the buildings have collapsed as well. Most of the human remains John sees are “light and old-sometimes they will fall into dust if you touch them” although he did find the body of one who had been well-preserved, his hand “like dry leather”. While describing the vision of the dead place before its destruction, John states that “for many years the poison was still in the ground”. Also, since John is able to remove metal from the dead places without becoming ill, enough time has passed for the metal to have lost its radioactivity.