Which region is located to the northeast of Georgia, known for its mountainous terrain?

The region located to the northeast of Georgia, known for its mountainous terrain, is the Blue Ridge. This area is characterized by its high elevations and rugged landscape, including the southern Appalachian Mountains. The Blue Ridge Mountains are part of a larger mountain range that extends through several states, and they are notable for their scenic beauty, rich biodiversity, and outdoor recreational opportunities.

In terms of geography, the Blue Ridge region features significant peaks, lush forests, and clear streams, distinguishing it from other regions in Georgia. The other options represent distinct geographic areas: the Plateau is generally flat and elevated, the Ridge and Valley has more rolling hills and valleys, and the Coastal Plain is characterized by low, flat land and is located to the south of the mountainous areas. Therefore, the Blue Ridge is the correct choice for the region known specifically for its mountainous terrain in northeastern Georgia.