[richardfey]

Notably missing from the page: any special landscape feature is likely to attract observation and achieve the opposite effect.

[bombcar]

Exactly what I was thinking.

Better to make it highly deadly or entirely hidden (with the warnings to be uncovered if you start excavating).

[hedora]

Yeah; I'd want to visit every one of these proposals on vacation.

The only exception is the one from Emil Kowalski. That proposal would make it so difficult to excavate the site that the civilization performing the excavation would likely have radiation detectors.

Step one in that is probably burying it sufficiently deep that it can't be found without advanced seismology.