One of the world's rarest and oldest maps went on display at the Library of Congress in Washington. It was made in 1602 by Italian priest Matteo Ricci, who visited China in the 1500s and taught the Chinese about the existence of "the Americas." The emperor asked him to make a map. The result is an enormous map, on five-foot-tall panels of rice paper, with China at the center. It's the first map in Chinese to show the land we now call North and South America.