All PA Trails of History sites are open FREE to the public to celebrate Pennsylvania’s birthday! This day commemorates the land grant made to William Penn from England’s King Charles II to settle a debt owed to Penn’s father. The land granted to Penn in 1681 eventually became the Commonwealth of Pennsylvania. PA Charter Day is always celebrated on the 2nd Sunday in March (Sunday March 12th in 2017). Please visit the PHMC Trails of History website or the PA Trailheads blog for more information about other interesting activities happening across the state on Charter Day.