Concrete block wall

Three concentric quadrilateral concrete-block walls: a solid masonry wall 21’4” on a side x 3’ high; a retaining wall 11’4” on a side x 4’4” high; and a center well or pit 4’ on a side x 5’ high; trench 52” wide x 4’4” high; tunnel 18” wide x 52” long x 30” high

Originally sited at Gibney Farm near New Kingston, PA