How Old Is This Building and What Happened There?

The other day when I took a walk, I noticed a strange building that was built in the old days.  There was a very strange sign on the side that said Bereaved Day of Prayer.  I have never seen such a sign like that in my life.  This must be a very old building with lots of history to it.  Does anyone know anything about this tower and what it was used for?   What was that sign about?    Check out my article on bubblews about this unusual building at:

http://www.bubblews.com/news/577320-very-old-abandoned-building-left-in-the-fields