International Day For Monuments and Sites is observed on April 18, 2021. The International Day for Monuments and Sites is held each year around the world with different types of activities, including visits to monuments and heritage sites, conferences, round tables and newspaper articles. The aim is to promote awareness about the diversity of cultural heritage of humanity, their vulnerability and the efforts required for their protection and conservation.
A monument is a type of structure either explicitly created to commemorate a person or important event or which has become important to a social group as a part of their remembrance of historic times or cultural heritage, or simply as an example of historic architecture. Monuments have been created for thousands of years, and they are often the most durable and famous symbols of ancient civilizations. (With material from: Wikipedia)