It is named for Lake Michigan, which makes up the eastern border of the County. The seat and largest city are both Waukegan.
It borders McHenry and Cook Counties in Illinois, along with Kenosha County in Wisconsin.
Main highways include I-41, I-94, US-12, US-14, US-41, US-45, IL-21 and IL-59.
Cities
Highland Park
Highwood
Lake Bluff
Lake Forest
Waukegan
Zion