The seat and largest city is Des Moines. In addition to being the most populated county in the state, it also holds State Capitol Des Moines.
It borders Boone, Story, Jasper, Marion, Warren, Madison and Dallas Counties.
Main highways include I-35, I-80, I-235, US-6, US-65, US-69, IA-5, IA-17, IA-28, IA-141 and IA-163.
Cities
Altoona
Ankeny
Des Moines
Mitchellville
Pleasant Hill
Polk City
Runnells
Urbandale
West Des Moines