Sure, so what we do is, as the other bit of my post said, make the material sufficiently difficult to get to that it would take a long time and an advanced civi

Sure, so what we do is, as the other bit of my post said, make the material sufficiently difficult to get to that it would take a long time and an advanced civilisation to be able to get to it, by which point they would have had plenty of time to figure out what the writing meant. We're not talking about a bunch of dudes with shovels here, we're talking about colossal industrial machinery or advanced explosives.