The 'old' viaduct over the Pétrusse, built between 1859 and 1861 to carry the new railway line from the Gare district up to the old town. The 290-metre brick arched bridge is overshadowed today by the bigger Adolphe Bridge a short distance west, but the Passerelle is the older, more elegant, and arguably the more atmospheric of the two.
The footpath underneath is part of the Pétrusse Park walk. Sunset is the moment to be on it.