NewsPopulation The 2 densest US counties = 1,437 least dense counties September 10, 2015 Alex This post may contain affiliate links. As an Amazon Associate, we earn from qualifying purchases. Related Posts:The Most Affordable ZIP Codes to Buy Property in…The Most and Least Expensive American NeighborhoodsGeography Facts About the U.S. CountiesPopulation Density and Urban Transit In Large World CitiesExploring America’s Drinking HabitsThe Most and Least Loved Occupations in the US and UKEvery U.S. State's Favorite Swear WordU.S. county etymology maps