sentences:  LaSalle County, Illinois
  
  LaSalle County is located in the North Central region of the U.S. state of Illinois; it has an estimated population of 108,669 as of 2019 and its county seat and largest city is Ottawa.LaSalle County is part of the Ottawa, Illinois, IL Micropolitan Statistical Area, which is also included in the Chicago-Naperville, IL-IN-WI Combined Statistical Area.