From the Vikings, the lords of the northern seas, to Amerigo Vespucci, who gave his name to an entire continent, America. From men like Marco Polo, who crossed the Silk Road and traveled to distant China, to women like Isabelle Eberhardt, whose life inspired books, movies, and even a lyrical opera, and Valentina Tereshkova, who orbited the planet 48 times in 70 hours!