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The sheer number of locks placed on the bridges added a significant amount of weight. The Pont des Arts in Paris, for example, accumulated so many locks that the combined weight became a serious structural issue, threatening the integrity of the bridge.

accumulated so many locks that the combined weight became a serious structural issue, threatening the integrity of the bridge.

Wow, I guess that's why after a certain time, these locks need to go. They sure play a memorable role in human life but threatening to the bridge structure...

Thank you for the explanation...

I see Browery already explained. I think this is why they removed them.
Maybe some conservation works had to be done and they were on the way.