
Honestly, even now I don’t know why people made some of them, especially spines that are on hand-rails near street-doors. Although I can’t imagine what is the usage of them, I can easily make up how they hurt you when you are trying come in. It seems that nails were created in the same time as the buildings were, I think there was dangerous time with terrific customs.

To support my observations you see here pictures, which have been captured in Amsterdam during my holidays in spring 2009.

Look forward to seeing comments from you. Why they did make the nails on hand-rails?