Cetralized web configuration using <location/> attribute

On my current project we have 3 virtual directories configured as separate applications. Each has its own web.config not knowing it is possible to have only one web.config for all those application on the root directory's web.config. This was made possible thru the &lt;location/&gt; attribute. With &lt;location/&gt; I had centralized configuration which makes administration and creation of installer easier.