|For those who would like to visit the place where the Mason-Dixon line begins, here below is a map that may be helpful.
You get to the area by taking I-95 to the Delaware and Northeastern Maryland area. Look for the exit to 896. Take 896 North, through New Castle County, Delaware.
You can make a right turn on a road which will pass into the "Whiteclay Creek" preserve and go right by the "Arc Corner." Unfortunately the road is not marked on this map, but trust me, heh heh. No, really. To the eastern side of the road (if you're driving northerly) you'll see a granite obelisk about 5 feet high marking the Arc Corner. There is a small turn-off on one side of the road you can use for parking.
Alternatively, you can drive into Pennsylvania on 896, looking for a right turn on Chambers Rock Road---which IS on the map below, less than a mile from the state line. Go east until you reach Arc Corner road, make a right, and travel downhill c. 1 mile. The road will gradually give way to gravel and then to a path, so you'll have to find a place to park. If you follow that path, you'll eventually emerge at the paved road described in the previous paragraph and--across that paved road--can discover the Arc Obelisk Marker.
The northernmost segment of the "Tangent Line" that gave poor M&D so much hassle is also shown on the map below. It is the Delaware/Maryland border line, here marked as the border between Cecil County, Maryland, and New Castle County, Delaware. This line was supposed (by King's and Colonists's orders) to both be a Line running due North AND be a perfect tangent line just touching the Arc at its westernmost point, creating a perfect N/W right angle. But as Pynchon's book shows, the "perfect" abstractions of Euclid and Enlightenment science, not to mention the designs of imperial empires, fail to coincide with a complicated world, and poor Mason and Dixon have to compute the difference. Here, that difference is marked on the map by the Delaware "wedge," the space (which includes Whiteclay Creek) to the left of the Arc Corner which makes up the northwest section of Delaware.
The whole area is great for driving, hiking, and mountain-biking.
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