Strange Neighbors

The border between Delaware and Pennsylvania is a perfect curve.
It’s the arc of a circle centered on the cupola of the courthouse at New Castle.
It’s the only such boundary in the territorial United States.
An idler's miscellany of compendious amusements

The border between Delaware and Pennsylvania is a perfect curve.
It’s the arc of a circle centered on the cupola of the courthouse at New Castle.
It’s the only such boundary in the territorial United States.