Our Lady of Perpetual Help - Salem, Est. 1947 In Roanoke County, beginning at the intersection of the Roanoke-Botetourt County lines and Interstate 81, southwest on I-81 to Mason Creek, south along Mason Creek to the Roanoke River, east along the Roanoke River to the Salem town-Roanoke County line, south and west along the Salem town-Roanoke County, Salem-Roanoke city, Salem-Roanoke County lines to the Catawba-Windsor Hills magisterial district line, south along the Catawba-Windsor Hills district line to the Roanoke-Montgomery County line, north along the Roanoke-Montgomery, Roanoke-Craig County lines to the Roanoke-Botetourt County line, east along the Roanoke-­Botetourt County line to Interstate 81, which is the starting point.