The existence of several historical and Quaranic inscriptions in Arabic script have facilitated setting the chronology of Taj Mahal. The Taj Mahal is considered to be the greatest architectural achievement in the whole range of Indo-Islamic architecture. The uniqueness of Taj Mahal lies in some truly remarkable innovations carried out by the horticulture planners and architects of Shah Jahan. IntegrityIntegrity is maintained in the intactness of tomb, mosque, guest house, main gate and the whole Taj Mahal complex. The TTZ comprises of 40 protected monuments including three World Heritage Sites - Taj Mahal, Agra Fort and Fatehpur Sikri.