BEGIN WV 121: 0 - 0
WV 54, WV 97: 3.8 - 3.8
WV 16, WV 97: 0.3 - 4.1
Creation: Appeared about 2005 as new construction running as it does today. This is the only WV 121.
Adjustments: WV 121's extension to WV 54 near Mullens has been graded but not paved to just inside Wyoming County and is not open to traffic. Construction to get the road to WV 54 and actually pave the route is expected to begin in 2018.
Improvements: Upon designation, WV 121 was fully paved and a 4-lane expressway.
Comment: WV 121 is the Coalfields Expressway, a road that is intended to reach Welch and extend west into Virginia before ending at US 23 Pound VA.
WV 121 is the placeholder designation for US 121 which will be assigned to the Coalfield Expressway at some point (my guess would be this might take place when the road reaches US 52 Welch OR if Virginia builds its segment from US 23 to US 460 first.
No matter who does what first, the Coalfields Expressway is a long, long way from being fully finished in West Virginia. The only other parts that have had any work is a 1-mile segment behind the McDowell Federal Correctional Center has been graded but not paved.
WV 121's open segment
2017 Raleigh County