mosques, or parts used to build mosques. There exist both Indian and Muslim traditions of religious toleration. Muslim rulers led campaigns of temple destruction and forbade repairs to damaged temples, following the Muslim traditions. The Delhi Sultanate destroyed a large number of temples; Sikandar the Iconoclast, Sultan of Kashmir, was also known for his intolerance. The 16th- and 19th-century Goa Inquisition destroyed hundreds of Hindu temples. All Hindu temples in Portuguese colonies in India were destroyed, according to a 1569 letter in the Portuguese royal archives. Religious conflict and desecrations of places of worship continued during the British colonial era. Historian Sita Ram Goel's book "What happened to Hindu Temples" lists over 2000 sites where temples have been destroyed and mosques have been built over them. Some historians suggest that around 30,000 temples were destroyed by Islamic rulers between 1200 and 1800 CE. Destruction of Hindu temple sites was comparatively less in the southern parts of India, such as in Tamil Nadu. Cave-style Hindu temples that were carved inside a rock, hidden and rediscovered centuries later, such as the Kailasa Temple, have also preferentially survived. Many are now UNESCO world heritage sites. In India, the Place of Worship (Special Provisions) Act was enacted in 1991 which prohibited the conversion of any religious site from the religion to which it was dedicated on 15 August 1947. Customs and etiquette The customs and etiquette varies across India. Devotees in major temples may bring in symbolic offerings for the puja. This includes fruits, flowers, sweets and other symbols of the bounty of the natural world. Temples in India are usually surrounded with small shops selling these offerings. When inside the temple, devotees keep both hands folded (namaste mudra). The inner sanctuary, where the murtis reside, is known as the garbhagriha. It symbolizes the birthplace of the universe, the meeting place of the gods and mankind, and the threshold between the transcendental and the phenomenal worlds. It is in this inner shrine that devotees seek a darsana of, where they offer prayers. Devotees may or may not be able to personally present their offerings at the feet of the deity. In most large Indian temples, only the pujaris (priest) are allowed to enter into the main sanctum. Temple management staff typically announce the hours of operation, including timings for special pujas. These timings and nature of special puja vary from temple to temple. Additionally,