ABSTRACT Katherine Greacen Nelson (1913–1982) achieved many firsts in her career, but sharing her enthusiasm for geology was first and foremost to her. As the first child born into a military family in 1913, Katherine Fielding Greacen was exposed to nature and travel at an early age. By 1934, she received her bachelor degree from Vassar College, winning a prize for excellence in geology. Just four years later, she received the first Ph.D. in geology from Rutgers University and was the first woman awarded a doctorate in any discipline at that school. Soon after, Katherine was hired by Milwaukee-Downer College as the geology/geography department and curator of its Greene Museum. She left campus for the Texas oilfields in 1943 to do her part for the war effort, working as a petroleum geologist and paleontologist. Having returned to Milwaukee-Downer in 1946, she left again in 1954. The newly founded University of Wisconsin–Milwaukee (UWM) acquired the Milwaukee-Downer campus in 1956, and Katherine became the first faculty member and chair of the geology department. She later brokered the purchase of the Greene collection for UWM and established a public education program at the museum. Serving many professional societies and lay organizations throughout her life, Nelson was the first woman president of the Wisconsin Academy of Sciences, Arts and Letters in 1952, and the first woman to receive the Neil Miner Award from the National Association of Geology Teachers in 1978. Throughout her career, Katherine’s mission was to help people understand their surroundings, appreciate geologic time and processes, and feel awe for all that has gone before. To these ends, she put her effort and energy into reaching the widest audience by presenting public lectures, helping geology hobbyists, giving museum tours to schoolchildren, writing popularized articles, and giving media interviews. She even explained the importance of Wisconsin’s glacial features to politicians to help establish the Ice Age National Scientific Reserve. Katherine especially enjoyed taking students into the field, many for their first exposure to the landscape. As a result, she inspired generations of students to share their (and her) knowledge and enthusiasm, which continues to support her goal of putting the appreciation of geology and the landscape on par with cultural pursuits.