All over China and in many of its most holy places you can find massive amounts of these engraved locks hanging off of chain railings, fences, and bridges. Sometimes these are referred to as Love Locks. The idea being that you lock your love away and it will never be broken.
In China it seems that this very old tradition is more than that. People engrave the locks with personal hopes, dreams or things they wish to let go of. They lock it away as a symbol of their commitment.
This practice is spreading all across the globe and while it is an interesting symbol of humanities desire to change it comes with unintended consequences. The locks rust and create environmental risks to an area. The locks can become a hazard as the sheer weight can compromise the railings and especially the bridges they are hung on. In many European cultures they have removed the locks and put up signs letting visitors know that the practice isn’t allowed in certain areas. This seems like an odd tradition that perhaps our global population has outgrown, but still a beautiful one.