After the fall of Rome, as civilizations collapsed and libraries burned, ancient knowledge that would eventually fuel the Renaissance was at risk of being lost. This thrilling history tracks three crucial books as they were passed hand to hand through seven cities during a perilous thousand-year journey of survival. After the great library at Alexandria was destroyed, Baghdad, Cordoba, Toledo, Salerno, and Palermo were rare outposts of knowledge in a dark world, where dedicated scholars collected, translated, and shared texts. Violet Moller’s The Map of Knowledge takes us into the sparkling intellectual life that flourished there, highlighting the crucial role played by Arab scholars in improving the cornerstone ideas of Western thought. She shows us how foundational works on math, astronomy, and medicine by Euclid, Ptolemy, and Galen eventually reached Venice, the major center of scientific printing, where their legacy was assured—having been rescued by the passionate curiosity of generations of readers.