An important site that is marked and preserved as public property WordNet 3.0 & Open English WordNet

A monument is a type of structure that was explicitly created to commemorate a person or event, or which has become relevant to a social group as a part of their remembrance of historic times or cultural heritage, due to its artistic, historical, political, technical or architectural importance. Wikipedia

Structure commemorating a person or event. Wikipedia Disambiguation

Type of structure either explicitly created to commemorate a person or important event, or used for that purpose Wikidata