Have you ever wondered why bodies are buried 6 ft deep? There are a number of reasons. Six feet of soil would stave off the odor of the corpse as well make it difficult to easily rob a grave. However, the main reason was that it prevents an animal for savaging the body.

6 ft isn’t the maximum depth either. In large European towns where space was limited, multiple interments were once made in a single grave. These graves could be dug as deep as 9 meters (30 ft), and the coffins were piled on top of each other. This was done for families who could not afford multiple grave sites. (Source)