monument

As a noun monument

is monument.

As an adjective monumented is

marked by the positioning of a monument, often in the form of a small stone or concrete structure.

As nouns the difference between monument and runestone

is that monument is monument while runestone is (archaeology) an ancient monument consisting of a (raised) stone with a runic inscription.

As nouns the difference between monument and topograph

is that monument is monument while topograph is a monument erected in a high place, such as a hilltop, indicating the direction and distance of notable landscape features which can be seen with the naked eye from that point.