For those that are not aware, the Parade Square (or Parade Ground) is a very important place to anyone that has served.
After a battle, when the retreat was sounded and the unit had reassembled to call roll and count the dead, a hollow square was formed.
The dead were placed within the square and no-one used the area as a thoroughfare.
Today, the parade ground represents this square and hence, a units dead.
It is deemed hallowed ground, soaked witht the blood of our fallen and the area is repsected as such by all.