Mainz is the place where Johannes Gutenburg develped the printing press that changed the world. We toured the museum and saw the first printed bible. The most precious pieces on display at the museum are the original 42-line Bibles dating from 1455. These Bibles are considered the first-ever printed books using Gutenberg’s technique. Up until 1455, Bibles were hand-written by monks and the process took as long as 20 years. With the help of moveable letters, mass production was on its way. Understandably, they wouldn't allow photos inside the museum.