Subregions of Mercer County
So far Mercer County has
2 played regions below it. Following direct parts of Mercer County have been played so far:
Sibling Regions of Mercer County
Other played regions in the hierarchy of Mercer County until now:
Unruled Sibling Regions till now: Beaver County,
Berks County,
Chester County,
Crawford County,
Delaware County,
Fayette County,
Greene County,
Philadelphia County,
Warren County,
Washington County,
Westmoreland County.
Badge(r)s! 
(Only makes a difference if you play the game. Otherwise never mind.)
Allegheny County 
Erie County.
Mercer County