Moseley Wrought Iron Arch Bridge  The Moseley Wrought Iron Arch Bridge, also known as the Upper Pacific Mills Bridge, is a historic, riveted, wrought iron bowstring arch bridge now located on the campus of Merrimack College in North Andover, Massachusetts. It was added to the National Historic Civil Engineering Landmark list in 1998  and was originally part of the North Canal Historic District on the National Register of Historic Place. It is the oldest iron bridge in Massachusetts, and one of the oldest iron bridges in the United States. It was the first bridge in the United States to use riveted wrought iron plates for the triangular-shaped top chord. The bridge was completed in 1864 as Moseley Truss Bridge built by the Moseley Iron Building Works of Boston, to connect the Pacific Mills with Canal Street in Lawrence, Massachusetts by spanning the North Canal. It partially collapsed in the late 1980s, but in 1989 it was removed to the Merrimack College campus in North Andover and was rehabilitated under the direction of Francis E. Griggs, Jr., Professor of Civil Engineering. It was placed over a campus pond as a footbridge, and was rededicated in this new location on October 23, 1995.