https://www.pcgamer.com/fallout-76s-map-is-called-appalachia-bethesda-confirm/

Fallout 76's map is called Appalachia, Bethesda revealed this week. In real life the Appalachian region, which contains the Appalachian Mountains, stretches up the Eastern US, from northern Alabama to southern New York state. West Virginia, where we already knew the game is set, sits fully within Appalachia, so the name isn't a huge surprise. 

Even if you're not familiar with the region you might have heard of the Appalachian Trail, the world's longest hiking-only footpath. I'd be surprised if it didn't make it into the game in some capacity.