VA 23: Began in January 1918 as an original state route defined by the general assembly:

Route 23: Stuart, Floyd, Christiansburg, Blacksburg, Pearisburg, West Virginia Line
So initially VA 23 ran from VA 12 (now US 58 Bus) Stuart to the West Virginia Line at Glen Lyn.
It is unclear how VA 23 ran from Pearisburg to West Virginia, but in Dec 1922 (CTB), VA 23 was defined to go through Narrows and remain south of the New River to Glen Lyn.
In March 1922 (CTB), there is reference to appealing a court ruline on the location of VA 23 from Christiansburg south. It appears VA 23 was initially sent via Pilot to Floyd via today's SR 615. Maps after this show VA 23 going via Riner.
In Dec 1923 (CTB), VA 23 was rerouted at Narrows to cross the New River and go via Rich Creek to the West Virginia line at Narrows. The old way has been secondary ever since and is now SR 649.

VA 23 south of New River west of Narrows 1923 Official

VA 23 via Rich Creek 1926 Official

In March 1924 (CTB), VA 23 was extended south as new routing to the North Carolina Line.

VA 23 south ending at Stuart 1923 Official

VA 23 extended to NC 1924 Official

Around 1926, VA 23 was removed from SR 796 Old Newport Rd. Around 1929, VA 23 was removed from Eagle Dr/Thomas Dr loop west of Pearisburg. In 1931, VA 23 was removed from SR 862 Grace Lane NE north of Floyd; also removed from SR 678 Valley View Church Rd and the southern part of SR 671 in Riner. In 1932, VA 23 was removed from SR 695 just north of Floyd; also by 1932, VA 23 was removed from SR 642 Triangle St south of Blacksburg. In July 1933, VA 23 was renumbered as VA 8. Today, the last routing of VA 23 followed VA 8 from NC to Christiansburg, except these loops in Floyd County: SR 773 Elephant Curve Rd; SR 794 Lumber Ln; Nursery Ln; Wade Hill Rd; Carriage Rd. VA 23 used College St into Christiansburg, then Depot St to VA 111 north back to US 460 Business leaving Christiansburg; Airport Rd (no longer connects back to US 460 Bus) to Blacksburg; SR 683 Giles Rd; Then US 460 to West Virginia except: abandoned alignments over Walker Mtn; SR 797 and VA 42 to Newport; SR 798; SR 783 through Maybrook; SRs 777-778 in the Sinking Creek area; SR 771 at Hoges Chapel; SR 1404 through Pembroke; SR 636 in Ripplemead; SR 806 and US 460 Bus in Pearisburg; VA 100 to Narrows; VA 61 across the New River; US 460 then SR 806 in Rich Creek; then a long abandoned piece; SR 1306 to US 460; SR 648 Ball Ave

VA 23 convoluted in Christiansburg/Cambria 1932 Montgomery County

VA 23 TEMP: During the dispute concerning how to route VA 23 from Floyd to Christiansburg, neither route was able to be maintained by the state. So in March 1923, the General Assembly placed the road from Floyd to VA 3 (now SR 615) Starkey into the state highway system to give Floyd County residents a state-maintained ingress/egress.
In 1924, this became VA 232. Today it is the US 221 corridor.