sentences:  The major rivers of Alleghany County are the New River, and the Little River; the latter flows through the town of Sparta, the county seat.Isolated by mountainous terrain from the remainder of North Carolina to the east, Alleghany County was described in the 19th and early 20th centuries as one of the Lost Provinces of North Carolina.Due to its elevation, Alleghany County enjoys slightly cooler summers than the lowland areas to the east and south, with temperatures seldom rising over .