Pennsylvania Statutes Title 53 P.S. Municipal and Quasi-Municipal Corporations § 10602. County powers

The powers of the governing bodies of counties to enact, amend and repeal zoning ordinances shall be limited to land in those municipalities, wholly or partly within the county, which have no zoning ordinance in effect at the time a zoning ordinance is introduced before the governing body of the county and until the municipality's zoning ordinance is in effect.  The enactment of a zoning ordinance by any municipality, other than the county, whose land is subject to county zoning shall act as a repeal protanto of the county zoning ordinance within the municipality adopting such ordinance.