The lost heritage of iron bridgesin the eternal city

On 31 May 1853, after waiting two centuries and an half, it is finally inaugurated in the city centre of Rome, a few feet away from Capitoline Hill and the Forum, the walkway restoration of “Pons Aemilius”, achieved through an iron suspension bridge. It represents one of the first contributions to the knowledge of metallic construction in the Eternal City, whose building tradition was historically related to the use of brick and travertine. This construction begins an exceptional collaboration between Italian engineers and foreign specialists, mainly French and Belgian engineers, who will build within forty years several bridges with iron and cast iron structures down the Tiber, promoting through an imported know-how the introduction of different technological solutions according time after time to the features of the urban context. This condition is implemented through different support systems, from the suspension to the open sprandel arch bridge, or from the beam to the truss bridge, each one suitable for the reunification of separated parts of the city centre and the connection between areas where the future urban development will be directed. With the river banks refurbishment of the Tiber and the exponential increase of vehicle traffic already in the first years of the 20th Century, most of the iron bridges of Rome are being gradually replaced by bridges that use other constructive technologies, irremediably losing an heritage which was strongly linked to the international scenario of the time. The contribution, through archive sources and bibliographic documentation, tells the lost story of this precious heritage, rediscovering the strong relationship between the iron construction and the City of “Pontifex”.