The secretive mounds culture of the Eastern Woodland people is one of the many mysteries of the national parks.

An Effigy Mound American Indian culture developed over 1,000 years ago placing thousands of earthen mounds across the landscape of what (today) includes parts of Iowa, Wisconsin, Minnesota and Illinois.

The monument contains nationally significant archeological resources including (original) surviving examples of earthen American Indian mound groups that provide an insight into the social, ceremonial, political, and economic life of the Eastern Woodland people. Two hundred and six pre-European contact mounds are preserved here—of which 31 are effigies in the shape of bears and birds. Natural features in the monument include forests, tallgrᴀss prairies, wetlands, and rivers. As a sacred site to the modern descendants of the moundbuilders, park access is offered via fourteen miles of hiking trails.

Eastern Woodland Indians built mounds from about 500 BC until the early European contact period. A unique Effigy Mound culture developed in this area of the Upper Midwest placing thousands of mounds in the shape of animals across the landscape. Others are conical, linear, or compound shapes; many of the conical are burial mounds. Some effigy mound groups were built to a monumental scale; the Marching Bear Group, containing 10 bear and three bird effigies, stretches nearly one quarter mile along a bluff top overlooking the Upper Mississippi River.

At first you see low rises on the landscape, but soon your eye picks out regular patterns in the hills. Trace the patterns, and those hills turn into familiar shapes—animals rising out of the ground in low relief. The effigies aren’t nature’s work—American Indians created them between 850 and 1,400 years ago. American Indians built mounds at various times and places across the Americas, but only in the upper Midwest did a culture regularly build mounds seemingly shaped like birds, turtles, lizards, bison, and, most commonly, bears.

Why were effigy mounds created? They are best viewed from above, so who or what was meant to see them? With no written records and few surviving tribal stories and traditions, the mounds’ origin and meaning remain a mystery.

Effigy mounds have attracted the most attention but are not the area’s oldest mounds, nor were their builders the first to live here. Humans have lived in eastern Iowa for over 10,000 years. Dome-shaped conical mounds began to be built about 2,500 years ago by people now known as Woodland Indians.

By 1,400 years ago, in the Late Woodland period, area Indians began to build effigy mounds from just west of the Upper Mississippi River to Lake Michigan’s western shore. Locally this hunter-gatherer culture thrived on the rich resources of Mississippi waters, wetlands, and forests. From summer camps along the river they fished and gathered freshwater mussels, arrowhead roots, wild rice, acorns, fruits, and berries. White-tailed deer and elk were staple foods in winter when extended family groups lived in rock shelters in the local river valleys.

Earthen effigy mounds began to appear 1,400 years ago, and were possibly religious sites or clan symbols used in seasonal ceremonies. Some show evidence of fire, probably ceremonial, in the mound’s head, heart, or flank. Some tribal stories hold that the bear is the guardian of Earth and the bird the guardian of the sky. Perhaps the mounds were a means of connecting the people to the land and their spirit world and ancestors.

Around 850 years ago, the building of effigy mounds ceased. Archeological evidence suggests a major cultural transition: the people started to live in larger permanent villages, making new forms of pottery, and most significantly depending far more on agriculture than on hunting and gathering. Archeologists call the prehistoric people who took up this new way of life the Oneota Culture. It is believed that they are the ancestors of historic tribes in the effigy mounds region.

European explorers began arriving in the late 1600s. The fur trade among the Indians, French, British, and later Americans continued into the mid-1800s. The region saw a big influx of American settlers starting in the 1840s. Land with mounds was logged, plowed, and turned into farmland. In the early 1700s many held that technologically advanced cultures from the Middle East, China, or Europe had built the mounds, but Smithsonian Insтιтution research in the 1880s showed that the moundbuilders were prehistoric American Indians.

Surveys of northeastern Iowa in the 1800s and early 1900s documented the presence of over 10,000 mounds of all types. But within 100 years, fewer than 1,000 survived, and several people mounted efforts to preserve some of the remaining mounds. Effigy Mounds National Monument was established in 1949. Today, as you walk along the bluffs and around the mounds, be respectful of the ancient people whose relationship with nature inspired these creations.