If these are supposed to be hidden messages, they've done a good job.

[He pauses briefly to think. Maybe they're not forgotten...]

Maybe we weren't supposed to find these stories. They didn't want to forget them, but they didn't want to remember them either. These could be old records.

[Records of war and loss, so he imagines. History is painful, but history needed to be written and remembered in some way. The hidden history of this place could very well be carved upon these monoliths.]