It is named for Lake Michigan. The seat is Crown Point, while the largest city in terms of population is Hammond.
It borders Porter, Jasper and Newton Counties in Indiana, as well as Will, Cook and Kankakee Counties in Illinois.
Main highways include I-65, I-80, I-90 (Indiana Toll Road), I-94, US-6, US-12, US-20, US-30 and US-41 and US-231.
Cities
Atena
Crown Point
Gary
Hammond
Hobart
Munster
Schererville
Whiting