what county is blairstown nj in
Blairstown, New Jersey. Blairstown is a township in Warren County, New Jersey, United States. As of the 2010 United States Census, the township's population was 5,967 reflecting an increase of 220 (+3.8%) from the 5,747 counted in the 2000 Census, which had in turn increased by 416 (+7.8%) from the 5,331 counted in the 1990 Census.