Determination of an exact location for a West Jersey/East Jersey borderline was often a matter of dispute, but the old provinces correspond roughly with South Jersey and North Jersey today. The southern point of all of the lines is well north of Atlantic City, making that city part of West Jersey, though this may seem surprising since Atlantic City is on the east coast.
Remnants of the most operative line, run by George Keith, can still be seen in the county boundaries between Burlington and Ocean, and between Hunterdon and Somerset. The Keith line runs NNW from the southern part of Little Egg Harbor, passing just north of Tuckerton, and proceeding up toward a point on the Delaware River just north of the Water Gap.
The Keith line did not agree with the deed that formally defined the boundary, the 1676 Quintipartite Deed, and later, more accurate surveys and maps needed to be made to resolve property disputes. This resulted in the Thornton line, about 1696, and the Lawrence line, 1743, which was adopted as the final line for legal purposes.
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