Just on its own the Hohenzollern Bridge is a joy to walk across: only accessible to train and foot traffic, the iron truss bridge provides lovely views of the Rhine and leads to the Gothic Cologne Cathedral, the city’s must-see landmark. But the Hohenzollern is also known for its love locks, a collection of tens of thousands of padlocks fixed to the railings. Legend has it that if a couple puts a lock on the bridge and throws the key into the Rhine their love will last forever.

Take a look at the most impressive bridge in every US state and DC

The world's most magnificent bridges: which UK ones made our list?