>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.
The form of the danger is an emanation of energy.
The danger is unleashed only if you substantially disturb this place physically. This place is best shunned and left uninhabited.
Thought experiment, suppose in a remote part of the world, someone comes across a site with this exact message tomorrow and tweets it. What is the most likely scenario:
A) People heed the message and avoid the area.
or
B) The place is overwhelmed with people trying to find some hidden treasure or have alien encounters, etc.
I would argue that scenario B, is much, much more likely.
For better or worse, curiosity especially about forbidden stuff has been a hallmark of humanity, and likely will be so into the future. All this sign will do is encourage people to come and try to find the treasure and the mysterious source of power.