As the Mississippian culture declined at the ceremonial center, ca. 1350 a new culture coalesced among people who lived in the swamps downstream. The Late Mississippian period (1350 - 1600 A.D.), also consisted of the Lamar Period, where natives built two mounds that have survived at that site, including a unique spiral mound. The Lamar period is composed of four distinct phases that lasted between the years 1375 and 1670. It is identified through unique ceramic design elements that were primarily produced during this period. These four phases were the Duvall, Iron Horse, Dyar, and Bell phases.