a hunter-gatherer society, the people of which occupied this area only a seasonal basis. Successive generations organized to build the complex mounds over a 500-year period. Their food consisted mostly of fish and deer, as well as available plants. Poverty Point, built about 1500 BCE in what is now Louisiana, is a prominent example of Late Archaic mound-builder construction (around 2500 BCE – 1000 BCE). It is a striking complex of more than , where six earthwork crescent ridges were built in concentric arrangement, interrupted by radial aisles. Three mounds are also part of the main complex, and evidence of residences extends for about along the bank of Bayou Macon. It is the major site among 100 associated with the Poverty Point culture and is one of the best-known early examples of earthwork monumental architecture. Unlike the localized societies during the Middle Archaic, this culture showed evidence of a wide trading network outside its area, which is one of its distinguishing characteristics. Horr's Island, Florida, now a gated community next to Marco Island, was excavated by Michael Russo in 1980. He found an Archaic Indian village site. Mound A was a burial mound that dated to 3400 BCE, making it the oldest known burial mound in North America. Woodland period The oldest mound associated with the Woodland period was the mortuary mound and pond complex at the Fort Center site in Glade County, Florida. Excavations and dating in 2012 by Thompson and Pluckhahn show that work began around 2600 BCE, seven centuries before the mound-builders in Ohio. The Archaic period was followed by the Woodland period (circa 1000 BCE). Some well-understood examples are the Adena culture of Ohio, West Virginia, and parts of nearby states. The subsequent Hopewell culture built monuments from present-day Illinois to Ohio; it is renowned for its geometric earthworks. The Adena and Hopewell were not the only mound-building peoples during this time period. Contemporaneous mound-building cultures existed throughout what is now the Eastern United States, stretching as far south as Crystal River in western Florida. During this time, in parts of present-day Mississippi, Arkansas, and Louisiana, the Hopewellian Marksville culture degenerated and was succeeded by the Baytown culture. Reasons for degeneration include attacks from other tribes or the impact of severe climatic changes undermining agriculture. Coles Creek culture The Coles Creek culture is a Late Woodland culture (700–1200 CE) in the Lower Mississippi Valley in the