The Boyd Avenue Historic District is a residential district comprising 80 houses in Martinsburg West Virginia. The district includes the circa 1776 Aspen Hall and the associated Mendenhall's Fort of circa 1756. The district extends along Boyd Avenue 1500 feet (460 m) from West Race Street to Aspen Hall. The older section of the street is a single 40-foot (12 m) right-of-way while the newer portion is boulevarded with a grassed median between two separate roads. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
Building