Settle down, children, and I’ll tell you the strange history of the Delaware Wedge. You probably never heard of it, but Delaware, Pennsylvania, and Maryland have argued over it for more than 200 years.
It has been a long time since high school, so I’ll review the Mason-Dixon line, which is a prominent feature in all of this. It was surveyed between 1763 and 1767 and formed most of the boundary between Pennsylvania and Maryland (shown on the map at left, but unlabeled). The line, on the east side, then dropped south, then east again to the ocean to form the boundary between Maryland and Delaware. This Mason-Dixon survey was done to settle boundary disputes, but boundary disputes never end. Only later in the Civil War era was the line used to define the free Northern states from the slave-holding Confederate states.
The top of Delaware is a nominal arc, called the twelve-mile circle, radiating from the cupola on top of the courthouse in New Castle. Technically, it is not a single arc, but a composite of segments, each laid out separately, although no Delawarean will admit it. A good map will show the arc as slightly choppy, as it is.
The twelve-mile circle was meant to join at the corner where the Mason-Dixon line turned south, but inaccuracies in the survey caused it to fall short, creating this tiny wedge that has been argued over ever since. (I am not finished with the Wedge and will come back to it.)
A quick digression: The east boundary of Delaware is the Delaware River, but in the vicinity of the arc, the boundary is along the banks of the New Jersey side, not in the center as you would expect. This is spelled out in the specifications for the arc. Above the arc, between Pennsylvania and New Jersey, the boundary is in the center of the river, as usual, and the boundary moves back to the center south of the arc, a Little below the Commodore Barry Bridge about where Alloway Creek in New Jersey feeds into Delaware Bay. So, in the northern part of Delaware, the entire width of the Delaware River belongs to Delaware.
(Sometime in the recent past, New Jersey created a landfill that stuck out a little into the river, and that part belongs to Delaware. In my kayaking days, I have stood on that piece of land and looked across the river to New Castle, secure in the knowledge I was a legal resident of Delaware standing on Delaware territory. From a distance, the New Jersey police still yelled at me to get off, and I did, figuring the principle was not worth a fight. It is not my job to educate them.)
This legal position of the boundary in the Delaware river is not a trivial matter. In 2012, New Jersey wanted to build a pier for offloading ships carrying liquefied natural gas (LNG). Even though it was to be on the New Jersey side, the pier would extend into the river where it would be in Delaware territory. Delaware successfully halted the project, but it took a decision by the Supreme Court. The story ended happily for everyone as falling gas prices made the proposed pier impractical, and the plan was not pushed to fruition.
But now back to the Wedge. The Wedge is roughly triangular in shape with an area less than a square mile. It is only about 3/4 of a mile wide at the top and 3 miles long. That’s tiny, even for Delaware. As viewed on Google Earth, the Wedge seems to be populated now with tony estates.
Maryland clearly had no legitimate claims to the Wedge. William Penn owned both Pennsylvania and Delaware, so he was not overly concerned about the accuracy of the boundary between them. The controversies came later from others.
Court decisions have since given the Wedge to Delaware, who long assumed ownership, anyway. You can see its remains on a map as a little shelf of land on Delaware’s NW corner. This shelf was a quick fix and is only an extension of the true Mason-Dixon line. The court acted wisely. If they had given the Wedge to Pennsylvania, we would forever have to explain that little icicle of land hanging down.
Very recently, a Tri-State Monument was placed at the NW corner of the Wedge, I suppose to commemorate the stubbornness of politicians. I could find nothing on the Internet about it, but a trustworthy friend says he saw it.
That’s enough for today’s lesson, kids. Now you should at least know where the Wedge is and how it came about. If anyone gives you an argument about it, just walk away. It is only important to those who wallow in the cesspool of trivia. It is what it is, I kid you not.