Why is preservation of ancient monuments of India important?

Indian monuments, Indianetzone.com

Monuments of India.  SlideShare
As India happens to be one of a few countries, known for the oldest civilization, we have  thousands of monuments, 
heritage sites spanning  several centuries across India. None 
of the countries in the world  has this kind of variety quite
overwhelming, unique in  style and character native to the region relevant to that particular time in history. The pages of history, heritage and ethos are  frozen in these monuments and it is imperative that they should be well preserved for our posterity to help them understand the evolution,  growth and development of our civilization and society. Our monuments come under many categories, religious, historical, cultural and colonial, etc. Ironically, the undeniable fact is neither the governments - central/ state nor the like-minded organizations have understood the value of these monuments and heritage sites and the need of concerted efforts by them under the expert advice of conservationists and  groups to maintain them periodically. That we've grown blase and apathetic toward our rich cultural legacy and history shows our lethargic mind set. 
Indian monuments. LearnFrenzy
The Archaeological Survey of India (ASI), founded by Sir Alexander Cunnigham in 1861 soon after Sepoy Mutiny, and presently functioning under the Ministry of Culture, is a major Central government organisation. It is their responsibility to take care of India's ancient   monuments  by way of  maintaining, restoring and  protecting  them. The shocking news is ASI  openly admits 35% of the monuments/artifacts  under its control / management have either disappeared or fallen into ruins  due to sheer callous attitude on the part of officials. According to Comptroller and Auditor General, the official auditor of India’s public sector, the World Heritage sites in India are being poorly taken care of  by the Archaeological Survey of India. Of the 3,678 historical structures in India, the auditor surveyed a sample of 1,655 monuments  way back in 2013. The gist of their complaint is: appropriate care is not  taken by the ASI to protect them.  There are numerous cases of encroachment and unauthorized constructions in and around these sites. Some sites have become garbage dumps and parking space  for vehicles. In many places  on the outer walls one can see political party slogans or cinema posters. In many of these sites graffiti is a menace and the local council or municipality does not take any stringent action against the violators.  Since they are not barricaded and fenced with severe warning, vandals, hooligans and drunks are responsible for  causing damages  to the structures.   It simply means the officials have failed to do their duties  and  in them are lost  part of our diverse  cultural history and  past glory and this creates a hiatus in the  chronology of history. 

Historic site or Heritage site is an officially recognized  location where pieces of political, military, cultural, or social history are  preserved as they carry  cultural heritage value.  Such historic sites in the form of  building, landscape site or structure that is of local, regional, or national significance are usually protected by  special law, imparting official national historic site status. Visiting  such heritage sites  gives the people a great excitement and, most importantly,  a sense of nostalgia for bygone eras replete with unforgettable events, and  a keen desire  to learn about their cultural, social heritage, etc., relevant to the historical context of the site.
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Since there are thousands of monuments across India under the ASI management, it is a tough job for them to repair and restore them because it is to be done by expert guidance and it is essential that regardless of work to be undertaken, at any cost, the heritage value of the structure should not be tampered with or damaged. The ASI has neither the man power nor financial resources to carry on the restoration work. However, they can at least  keep track of the monuments/heritage sites that need immediate attention. They can demand additional funds from the central government  and also seek the cooperation of  like-minded people and organization in the restoration work.  
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As mentioned in the  ASI (Archaeological Society of India) manifest, serious attention must be paid to the following to protect the existing heritage sites:

01. In any restoration  of monument, priority should be given to the original work and  anything of heritage value should be saved  as much as possible. 

02. Efforts should be made to preserve and restore remnants or damaged original works  as they help the researcher understand the nature of the site by putting the pieces together - something like solving the zigzag puzzle. 

03.  Due attention is to be given to every structure on the site. Be they small or big care should be taken to repair and protect them. 

04. In addition to the  ASI's efforts, public cooperation is a must. Locally, with support from government organization, they should safeguard the heritage sites and raise funds to preserve them for posterity. So, public initiative plays a vital role and will impact the tourism in that area. 

05. When major repairing and restoration work becomes a necessity,  the heritage value of the structure should not be disturbed. It means  a through knowledge of the materials and methods used by the  ancient builders  is important and  it will retain old value and character of the site involved.

06.  Such restoration work needs to be done  under expert guidance of  conservationists who know the right materials and right methods to be used matching the old construction work.  Clay mortar is one of the oldest binding materials  widely used and such structures had a long life-span.

07.  In many old buildings indigenous construction materials were widely used. Mention may be made of  surkhi (crushed bricks ), batasha (sweet sugar drops), urad ki dal (white lentil), egg white, malai (cream), tambakoo sheera (juice of tobacco which was used from Akbar’s reign onward as an adhesive), and bel giri (Aegle marmelos) were added to the lime. In Tamil Nadu, Nayaks and Maratha rulers  used ground lime, clay mortar  mixed with jaggery and kadukkai for brick buildings. 

08. When using chemical treatment, proper care must be taken to use right chemicals. Improper chemicals may leach, fade away and mar the the original work. 

09. when dealing with cracks in the monuments  caused my minor tremors, root wedging as a result of growth of bushes, wild plants and trees, frost  wedging due to daily change of hot and cold  weather condition, and pealing of outer plastering,  special methods should be used to strengthen them. 

Besides above,  the ASI's central and state divisions  should consider the following when repairing and restoring buildings/structures of antiquity:

10. Comprehensive assessment of restoration work needs to be done before undertaking any major renovation work. No compromise should be made either on the quality of work  or on the heritage aspects of original work. High-pressure water and sand-blasting may damage delicate sculptures and artifacts. Like-wise chemical cleaning should be done carefully as structures like the Taj Mahal are quite sensitive.

11. In Tamil Nadu there is a need to protect the heritage site by way of installing strong fences and barricades around the heritage sites to prevent trespassing by unwanted people.

12. In Tamil Nadu, the ASI should come up with special programs to protect the old Hindu temples and the idols of deity made of five metal alloy (ayyempon) including gold. The metal idols of Chola king Rajarajan II, the builder of Big Temple, Thanjavur, TN that were stolen several decades ago were returned to the temple a few months ago  after an intensive  investigation. These are worth crores of rupees. Protection of ancient idols of gods and goddesses is an urgent necessity.

 India, being an ancient land, is rich in history. The overwhelming historic monuments provide ample scope for Heritage Tourism in which lots of tourists from India and abroad are interested. These places of antiquity reconnect the present generations with the aesthetic experiences of India's past history and rich cultural legacy  through time. It is the foremost duty of  the Indian government as well as respective state governments to save, restore and protect the invaluable monuments that are facing various threats. Time has come for the governments agencies to take action on the slowly dying monuments across India that go unnoticed. At this juncture, we can not afford to see them disappear slowly right under our nose.