Bible belt
The Bible belt is an area including a number of southern and midwestern states in the USA in which fundamentalist protestantism is a pervasive part of the culture. Although exact boundaries do not exist, it is generally considered to cover much of the area stretching from Texas north to Kansas, east to Virginia, and south to Florida.
The "belt" terminology is common in the USA to describe regions with a roughly east-west orientation that share a feature, such as the rust belt, a term to describe declining industrial areas of the northeast and upper midwest, and the sun belt, a term for hot-weather states stretching from coast to coast.