Since the late 20th century, archeologists have dated eleven sites in northern Louisiana where thousands of years ago, indigenous cultures built complexes with multiple, monumental earthwork mounds during the Middle Archaic period, long before the development of sedentary, agricultural societies. At sites such as Watson Brake, Frenchman's Bend, and Caney, generations of hunter-gatherers worked for hundreds of years to build and add to mound complexes. Hedgepeth Site, located in Lincoln Parish, is dated about 5200–4500 BP (about 3300–2600 BCE), from the latter part of this period. Such finds are changing the understanding of early human cultures.