you are likely to find Courtroom in/at/on City. City is a type of Place. Place is related to Park. Park is a type of Site. 
you are likely to find Water in/at/on Lake. Water is related to Whale. 
Courtroom --AtLocation--> City --IsA--> Place <--RelatedTo--> Park --IsA--> Site 
Lake <--AtLocation-- Water <--RelatedTo--> Whale 