NC 681: was born in 1928 as a renumbering of part of NC 68. It ran from NC 68-69 (current US 221 Bus/NC 88) Jefferson northeast to Crumpler then north to Virginia where the route continued as a secondary route to Mouth Of Wilson, VA. Note that in 1931 Virginia created VA 139 to meet NC 681. Oddly, there are several maps in the 20s that seem to show this connecting with the initial VA 123 which became VA 129, but that connection is not apparent in the 1930 Ashe/Alleghany maps or anywhere else...
NC 681 met its end in 1940, when NC 16 was extended over it, in the process of creating the NC-VA-WV 16 route we have today. However, NC 681's routing is not NC 16 now. NC 681 used SR 1573 Healing Springs Road, as NC 16 was totally rebuilt in the 1950's.

NC 68 north of Jefferson

NC 681 north of Jefferson

NC 16 north of Jefferson