Synonyms for monument

noun

1. Anything erected to preserve a memory

   tomb, tombstone, marker, shaft, column, pillar, headstone, gravestone, cenotaph, mausoleum, obelisk, shrine, statue, building, erection, pile, tower, monolith, tablet, slab, stone; see also memorial.

2. A landmark in the history of creative work

   work of art, magnum opus, exemplar, permanent contribution; see achievement 2, masterpiece.