Re:Warning signs for the year 10,000
by joe_the_user on Saturday February 12, 2011 @07:19PM
(#2211603)
Anything you create above ground will have to survive the equivalent of being sand-blasted for many weeks.
No sculptural details are going to survive. You can write symbols though, by mixing different colored concretes.
Although on the other hand, if there are above ground landmarks, then knowledge about what the place signifies is less likely to vanish.