Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Cahokia Mounds State Historic Site' has mentioned 'Valley' in the following places:
Occurrence Sentence Text Source
Located in Collinsville, Illinois near the city of St. Louis, this largest pre-Columbian settlement north of Mexico is the pre-eminent example of a cultural, religious, and economic centre of the Mississippian culture (800xe2x80x931350), which extended throughout the Mississippi Valley and the south-eastern United States.