Castalia (pronounded "Cas-tale-yuh", is a town in Nash County, North Carolina, United States. It is part of the Rocky Mount, North Carolina Metropolitan Statistical Area. The population was 340 at the 2000 census.
Castalia is located at 36°4′53″N 78°3′31″W / 36.08139°N 78.05861°W / 36.08139; -78.05861 (36.081258, -78.058682).
According to the United States Census Bureau, the town has a total area of 0.7 square miles (1.9 km²), all of it land.