To baseball fans, a mound is where the pitcher stands to throw the ball; to geographers and archeologists, respectively, it’s a rounded elevation or small hill, or an artiﬁcial mount or rounded earthwork made of piled stones or soil. Artiﬁcial mounds may be angular or rounded at their base, raised in the shape of a cone or a pyramid, but with a ﬂat top, or built up in the shape of an animal, a so-called totemic mound. Archeologists have studied a wide variety of mostly burial mounds erected by a succession of Native American cultures, beginning with Adena societies about four thousand years ago in the upper Ohio River valley. Adena structures were followed by a more diverse array of earthen mounds constructed on a much grander scale by societies of the Hopewell culture, who carried this architecture farther down the Ohio, to its conﬂuence with the Mississippi. With the decline of the Hopewell culture around A.D. 500, societies of the Mississippian culture further diversiﬁed mound building, and these massive and extensive forms— one Hopewell earthwork enclosed an area of four square miles—spread from the upper Mississippi River valley into the American South, as far east as New York State, and out into the Great Plains. Susan Brind Morrow describes such a site in upstate New York in her book Wolves and Honey: “The ﬁrst settlers to farm the land around Kanadesaga agreed not to disturb the burial mound of raw earth, ﬁve feet high and forty feet around, that stood in an open ﬁeld where a Mrs. Campbell, a captive from the massacre at Cherry Valley who was still alive among them, had witnessed one of the last of the Seneca tribal rituals: the sacriﬁce of a white dog at the end of winter.” Today, the range of artiﬁcial mounds, from simple structures that might have been built by just a few people in a day or two to structures that must have required the labor of thousands of people over a period of years, are preserved at such places as Mound City Group National Monument, Ohio; Efﬁgy Mounds National Monument, Iowa; and Ocmulgee National Monument, Georgia. The word is also widely used to refer to piles of soil created at tunnel entrances by burrowing animals such as gophers, badgers, prairie dogs, and coyotes.