SARAH WASSNER FLYNN is a long-time writer for National Geographic Kids. She loves writing, running, and triathlons. When she's not writing about races, she's usually training or competing in one. She also writes nonfiction books and articles for kids and teens, like The National Geographic Kids National Park Guide U.S.A., This Book Stinks, and The Girl's Life Guide to the Most Amazing You.

DIANE HARRIS CLINE is an ancient Greek historian with a joint appointment in history and classical studies. She is the author of National Geographic's The Greeks: An Illustrated History (2016) and she teaches ancient Greek history as well as digital history and digital humanities at George Washington University in Washington, D.C. She received her B.A. in Classics from Stanford and her Ph.D. in Classical Archaeology from Princeton University.