During clearance of my vfr flight plan, the controller cleared and requested I fly the vfr corridor over Lake Pontchatrain.  Since I did not know exactly what he was instructing, I requested I fly my filed plan direct to vor HRV then onto my destination.  He complied with my request.  After the flight I tried to find out what was the "vfr corridor"  and could not find it anywhere -- sectional chart, sids, etc.  Can some direct me to where I can find the information, or was the controller just going to give me vectors out of the class B area or is the corridor the victor route V20.