Earthworks (archaeology)
In archaeology, earthworks are artificial changes in land level, typically made from piles of artificially placed or sculpted rocks and soil. Earthworks can themselves be archaeological features, or they can show features beneath the surface. Earthworks of interest to archaeologists include hill forts, henges, mounds, platform mounds, effigy mounds, enclosures, long barrows, tumuli, ridge and furrow, mottes, round barrows, and other tombs. Hill forts, a type of fort made out of mostly earth and other natural materials including sand, straw, and water, were built as early as the late Stone Age and were built more frequently during the Bronze Age and Iron Age as a means of protection. See also Oppidum. Henge earthworks are those that consist of a flat area of earth in a circular shape that are encircled by a ditch, or several circular ditches, with a bank on the outside of the ditch built with the earth from inside the ditch. They are believed to have been used as monuments for spiritual ritual ceremonies. A mound is a substantial manmade pile of earth or rocks that was frequently created to mark burial sites Platform mounds are pyramid or rectangular-shaped mounds that are used to hold a building or temple on top. An effigy mound is a pile of earth, often very large in scale, that is shaped into the image of a person or animal, often for symbolic or spiritual reasons An enclosure is a space that is surrounded by an earthwork. Long barrows are oblong-shaped mounds that are used for burials. A tumulus or barrow is a mound of earth created over a tomb. A cross dyke or cross-ridge dyke is a bank and ditch, or sometimes a ditch between two banks, that crosses a ridge or spur of high ground. Found in Europe and often belonging to the later Bronze Age or Iron Age. Often marked on Ordnance Survey maps in the UK. Ridge and furrows are sets of parallel depressions and ridges in the ground formed primarily through historic farming techniques. Mottes are mound structures made of earth and stone that once held castles.