It would be a very appropriate message for the tombstone:

This place is a message… and part of a system of messages… pay attention to it!

Sending this message was important to us. We considered ourselves to be a powerful culture.

This place is not a place of honor… no highly esteemed deed is commemorated here… nothing valued is here.

What is here was dangerous and repulsive to us. This message is a warning about danger.

The danger is in a particular location… it increases towards a center… the center of danger is here… of a particular size and shape, and below us.

The danger is still present, in your time, as it was in ours.

The danger is to the body, and it can kill.