Hartland covered bridge - This structure, 390.75 metres long, is by far the longest covered bridge in the world. Covered bridges date from the first decade of the 19th century, when North American builders began using wooden trusses for long spans and covered them to prevent the truss joints from rotting. After 1840, the Howe truss, which introduced iron tension rods into the truss work, was widely adopted, and New Brunswick erected numerous bridges using this technique, among them this one, built in 1901.^[1] It was covered in 1922, after repairs to prevent new damage.^[2] The bridge is located in Hartland, New Brunswick, Canada