Which bridge in Porto, Portugal, was designed by Théophile Seyrig and opened in 1886?

The Dom Luís I Bridge in Porto was designed by Théophile Seyrig and opened in 1886.

The metal arch bridge crosses the Douro River between Porto and Vila Nova de Gaia. Théophile Seyrig, a former associate of Gustave Eiffel, won the design competition for the bridge. Its large double-deck iron structure reflects the engineering style of late nineteenth-century industrial Europe.

The upper deck originally carried road traffic and now carries Porto Metro trains, while the lower deck carries road traffic. Pedestrian paths run on both levels. This arrangement means the bridge has remained useful even as transport technology and traffic patterns changed.

The Dom Luís I Bridge is sometimes incorrectly attributed entirely to Eiffel because of its visual resemblance to other iron bridges associated with him. Eiffel designed the nearby Maria Pia Bridge, which opened in 1877; Seyrig designed Dom Luís I.