Dave Alt and Don Hyndman started the popular and long-lived Roadside Geology series in the 1970s, with the publication of Roadside Geology of Northern California in 1975. Dave Alt passed away in 2015, but his passion for teaching and his wry humor carry on in this revision. Donald W. Hyndman is dedicated to bringing geology to the general public, and cofounded the popular Roadside Geology series. He has written a number of the series titles with coauthor David Alt, and helps edit others. Katherine Baylor holds degrees in geology and geography from the University of California at Santa Barbara. She currently lives in Berkeley and works as a hydrogeologist for the U.S. Environmental Protection Agency. Kathy has traveled to over forty countries but always returns to California where she enjoys hiking, camping, and backpacking with her friends and family.