Silence can be so powerful. These are just a few of the Women in Black (click here or here). Every Saturday they are there. Rain. Sleet. Snow. Bitter cold. Hot sun. They are there. 

And the sign flashed out its warning
In the words that it was forming.
And the sign said, The words of the prophets are written on the subway walls
And tenement halls
And whispered in the sound of silence.

Simon and Garfunkel
The Sound of Silence 

Urban Simplicity.