The Ancient Monument preservation Act 2013 defines the "Ancient Monument" as follows: -
"Ancient Monument" means temple, monument, house, abbey, cupola, monastery, stupa, bihar etc, which have their importance above one century, from the point of view of history, arts, science, architectonics or art of masonry, and this word shall also mean the site of the monument as well as the human settlement or place, and remnant of ancient human settlement, relies of ancient monument, cave etc having specific value from the national or international point of view irrespective of the fact that such settlements or places are adjoining with each other or are separate in the same area.
The Department of Archaeology has been prepared the inventory of monuments of 75 districts. The ancient monuments are classified in three categories based on its importance - National importance, Regional importance and Local importance. These monuments belong to different periods from the Ancient period to the Shaha period and are located in different part of the country.