The body of water that marks the eastern edge of the Appalachian Mountain range is the Atlantic Ocean.

The Atlantic coastline, which runs along the Appalachians from the northeastern United States to the southeast, has had a significant impact on the climate, ecology, and culture of the region. On both sides of the mountains, this natural border supports a variety of ecosystems. The Atlantic Ocean plays a vital part in the region's economic activities, such as fishing and tourism, by supplying the neighboring states with water and necessary supplies. The shoreline is a well-liked location for both locals and tourists traveling through the Appalachian region because it provides recreational activities, breathtaking vistas, and picturesque surroundings.