Ponte do Freixo, Porto

Freixo’s surprise is that what reads as a single crossing is actually a pair of parallel bridge structures, separated by just ten centimetres. From a still spot on the pavement, you can take in the low roadway as it carries traffic across the Douro between Porto and Vila Nova de Gaia. Among the crossings linking those two cities, this is the one furthest upstream.

Its deck also sits lower than the other Porto–Gaia bridges, bringing the traffic close to the river’s level. The bridge opened in September 1995, created to ease the heavy vehicle queues that had been building at Arrábida and Luís I since the late 1980s. It gives drivers eight lanes in all, four in each direction; by 2011, its daily average reached 95,000 vehicles.

The crossing extends 705 metres in eight spans, with a 150-metre central span. António José Luís dos Reis designed it. This is infrastructure built for pressure: a deliberately broad, double structure that takes a major share of the city’s everyday movement while joining Porto to Gaia over the Douro.