If you haven't already or you are starting here, please read all the information posted in the description of the 1st hide in this series (Kev's Containers No. 1 : Masonvale).
This cache is hidden along the path behind Peterson hall.
But beware, there are muggles are everywhere.
This is the last in my series so far, will be expanding soon so keep on the lookout for more caches.