Effigy Mounds are ancient earthworks found primarily in the upper Midwest of the United States, particularly in areas like Wisconsin and Iowa. These mounds are shaped like animals, such as bears, birds, and snakes, and were created by Native American cultures, particularly the Mound Builders, between 1000 BCE and 1000 CE. They are believed to have served ceremonial purposes, possibly as burial sites or markers for important events. Today, Effigy Mounds are protected as part of the Effigy Mounds National Monument, which preserves these unique structures and the rich cultural history they represent. Visitors can explore the mounds through hiking trails, learning about the significance of these ancient sites and the people who built them.