The Arrowhead Library System (ALS) is the regional public library system that serves the seven counties in northeastern Minnesota, United States, It is geographically the largest public library system in the state. The seven counties served are Carlton, Cook, Itasca, Koochiching, Lake, Lake of the Woods, and St. Louis, for a total population of 308,012 people served. There are 29 member libraries in the system with a total of 2,392,726 items circulated in 2008.