Parallel 36°30' north
The parallel 36°30′ north is a circle of latitude that is 36 and one-half degrees north of the equator of the Earth. This parallel of latitude is particularly significant in the history of the United States as the line of the Missouri Compromise, which was used to divide the prospective slave and free states west of the Mississippi River, with the exception of Missouri, which is mostly north of this parallel.
In the United States, the parallel 36°30′ forms part of the boundary between Tennessee and Kentucky, in the region west of the Tennessee River and east of the Mississippi River. This parallel also forms part of the boundary between Missouri and Arkansas in the region west of the St. Francis River, and part of the boundary between the Oklahoma Panhandle and the Texas Panhandle. The rest of the boundaries between Virginia and North Carolina; between Virginia and Tennessee; and between Tennessee and Kentucky lie close to the parallel 36°30′. The boundary between Kentucky and Tennessee was defined as 36°30′, based on the Royal Colonial Boundary of 1665 that set the boundary of the Colony of Virginia and the Province of Carolina.
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