- Southern Terminus:
- Slab Fork Road (CR 34) in Slab Fork
- Northern Terminus:
- Robert C. Byrd Drive (WV 16) and Lester Highway (WV 54) in Crab Orchard
The Coalfields Expressway is a proposed highway through coal country in Virginia and West Virginia. When completed, it will be designated US 121 extend from US 23 in Virginia to the interchange of the West Virginia Turnpike (I-77) and I-64. So far, only a short portion in West Virginia has been completed, extending a few miles between Slab Fork Road (CR 34) and the interchange of Robert C. Byrd Drive (WV 16) and Lester Highway (WV 54). It is currently designated as a state route, WV 121, although it will be upgraded to a US route once more of the expressway is completed.