I have a two level patio. The raised level is 18" higher than the other. It currently has wood timbers that they want to get rid of which make up the retaining wall. I am going to install a modular block retaining wall in their place. One side of the wall that ran perpendicular to the house had a raised wooden bench connected to the retaining timbers. My idea was to take the retaining wall up into a freestanding wall then cap it for a seating area. Their concern is their grandchildren falling over it. How can I build something that can be a seating area but also have some sort of back to it to prevent a child from going over it? Another question is how sturdy would a wrought iron railing attached to the top of paver/cap of the retaining wall be? Any ideas that I'm not considering? Any pictures of something like this?