Fifty years after the ratification of the World Heritage Convention, we have come to learn that there is a huge discrepancy between the United Nations Educational, Scientific and Cultural Organization’s (UNESCO) ideals of protecting heritage sites with outstanding universal values and unmatched realities in situ. I attempt to elucidate what World Heritage ideals of heritage protection are held in iconic sites in Southeast Asia. The studied sites are ancient monumental heritage sites of national importance – namely, Borobudur of Indonesia, Sukhothai and Ayutthaya of Thailand, and Angkor of Cambodia. The authorities in these countries have converted heritage sites into parks for visitors and for capitalization, which has placed authenticity and integrity at stake as well as converting the sites for contestation between the authorities and local communities. In order to solve the dilemma of the World Heritage ideals and their unwanted realities, I explore possible effective approaches for UNESCO and its partners to take into consideration.