9730
Founded on the banks of the San Marcos River , the area is thought to be among the oldest continuously inhabited sites in the Americas .
 location: San Marcos River; location: Americas
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 location: San Marcos River; location: Americas