249838
A blockhouse was built as a refuge from Indian attack then various families built their cabins and the whole was surrounded by a strong timbered picket on three sides , the open side faced the river .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None