The Pont des Invalides is the lowest bridge traversing the Seine in Paris. The third bridge in this area, the Pont des Invalides was opened in 1855 for the World Fair in Paris.
The history of the Pont des Invalides reflects the dissonance between theoretical and practical vision in architecture and engineering. The first plans to build a bridge in this area featured a revolutionary suspension bridge, but they never fully came to fruition. The following bridge was demolished due to its instability; and the current one required serious renovation.
The story of this bridge started in 1821, when engineer Claude Navier conceived a technologically revolutionary bridge that crossed the Seine in one single reach without any point of support in between. The proposed suspension bridge, the construction of which started in 1824, was meant to be erected opposite to the Hôtel des Invalides on the site of the current Pont Alexandre III. Due to cracks in some parts of the bridge and gradual settling, the project was abandoned before the bridge even made it into service.
In response to complaints from the defenders of the Invalides perspective, the Public Services decided to shift the bridge site upriver. Therefore, in 1829, two engineers, de Verges and Bayard de la Vingtrie, completed the construction of a proper suspension bridge supported by two piers in the Seine and three porticos, each 20 metres in height. Unfortunately, due to rapidly growing wear on the bridge, its access had to be regulated in 1850.
In 1854, the bridge was demolished to be replaced by a new one in time for the upcoming 1855 World Fair in Paris. Paul-Martin Gallocher de Lagalisserie and Jules Savarin used the existing piers of the former suspension bridge and a newly added central pier to build an arch bridge in masonry on the same site. The new pier was adorned with sculptures in two allegorical themes: the “Land Victory” by Victor Vilain upriver; the “Maritime Victory” by Georges Diébolt downstream, whereas the two old piers were adorned with sculptures of military trophies bearing the imperial coat of arms, both the work of Astyanax-Scévola Bosio.
Despite being stronger, the new bridge still sustained a subsidence between 25 to 30 cm in 1878, and lost two arches during the winter of 1880 (restored by the end of the year). The bridge has been quite secure since then and the only modification made in the 20th century was the expansion of its pavement in 1956.