Mound

A mound is a pile of earth, gravel, sand, rocks, or debris. Most commonly, mounds are earthen formations such as hills and mountains, particularly if they appear artificial. A mound may be any rounded area of topographically higher elevation on any surface. Artificial mounds have been created for a variety of reasons throughout history, including ceremonial (platform mound), burial (tumulus), and commemorative purposes (e.g. Kościuszko Mound).

In the archaeology of the United States and Canada, a mound is a deliberately constructed elevated earthen structure or earthwork, intended for a range of potential uses. In European and Asian archaeology, the word "tumulus" may be used as a synonym for an artificial hill, particularly if the hill is related to particular burial customs.

While the term "mound" may be applied to historic constructions, most mounds in the United States are pre-Columbian earthworks, built by Native American peoples. Native Americans built a variety of mounds, including flat-topped pyramids or cones known as platform mounds, rounded cones, and ridge or loaf-shaped mounds. Some mounds took on unusual shapes, such as the outline of cosmologically significant animals. These are known as effigy mounds. Some mounds, such as a few in Wisconsin, have rock formations, or petroforms within them, on them, or near them.

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