( Encyclopedia of North American Indians) In addition, all along the Mississippi River valley are the remains of earthen mounds ​ — silent reminders that a thriving civilization once existed here.
( Encyclopedia of North American Indians) Selain itu, di sepanjang lembah Sungai Mississippi terdapat sisa - sisa gundukan tanah ​ — saksi bisu bahwa suatu peradaban yang berkembang pesat pernah ada di sini.