[1] The largest city is West Frankfort and the county seat is Benton.

[4] The high levels of gas found in Franklin County's coal deposits have resulted in mining disasters and explosions over the years.

1 mine, located in Zeigler, had an explosion that killed about fifty people.

[9] The West Frankfort quadrangle of Franklin County is home to 17 coal mines, according to a 2004 report.

[10] Wayne Fitzgerrell State Recreation Area is located in this county.

[11] On April 21, 1912, a tornado destroyed facilities at the Possum Ridge Mine.

The storm cut across the southern edge of the county, hitting West Frankfort and destroying most of the northern side of town, causing significant damage to the town's mining facilities.

As of the 2010 United States census, there were 39,561 people, 16,617 households, and 10,912 families residing in the county.