Shepherdstown is a town in Jefferson County, West Virginia, United States, located in the lower Shenandoah Valley along the Potomac River. Home to Shepherd University, the town's population was 1,734 at the time of the 2010 census.

Franklin County is a county located in South Central Pennsylvania. As of the 2020 census, the population was 155,932 Its county seat is Chambersburg.Franklin County comprises the Chambersburg–Waynesboro, PA Metropolitan Statistical Area, which is also included in the Washington–Baltimore–Arlington-DC–MD–VA–WV–PA Combined Statistical Area. It lies to a large extent within the Cumberland Valley.

Martinsburg is a city in and the county seat of Berkeley County, West Virginia, United States, in the tip of the state's Eastern Panhandle region in the lower Shenandoah Valley. Its population was 17,454 in the 2019 census estimate, making it the largest city in the Eastern Panhandle and the eighth-largest municipality in the state. Martinsburg is part of the Hagerstown-Martinsburg, MD-WV Metropolitan Statistical Area.

Frederick is a city in, and the county seat, of Frederick County, Maryland. It is part of the Baltimore–Washington Metropolitan Area. Frederick has long been an important crossroads, located at the intersection of a major north–south Native American trail and east–west routes to the Chesapeake Bay, both at Baltimore and what became Washington, D.C. and across the Appalachian mountains to the Ohio River watershed. It is a part of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area, which is part of a greater Washington-Baltimore-Arlington, DC-MD-VA-WV-PA Combined Statistical Area. The city's population was 65,239 people at the 2010 United States Census, making it the second-largest incorporated city in Maryland, behind Baltimore. Frederick is home to Frederick Municipal Airport (IATA: FDK), which accommodates general aviation, and to the county's largest employer U.S. Army's Fort Detrick bioscience/communications research installation.