Iron bridges: when engineering crossed the Douro

When the Dom Luís I Bridge opened in 1886, its 172-metre iron arch was the largest of its kind in the world. The double-deck structure, designed by Théophile Seyrig, transformed the crossing between Porto and Vila Nova de Gaia.

The bridge belongs to a family of metal structures that, in the second half of the nineteenth century, stitched the Douro valley together: railway viaducts, road bridges and industrial walkways on both sides of the border.

On the Bridges Route, iron stops being raw material hidden in the mountains and becomes a visible gesture of engineering — the link between mine, factory and city.