The Taj Mahal is India's most popular historical site, attracting approximately 6.2 million visitors annually. Other highly visited historical sites include Qutub Minar in Delhi with about 3.
Pollution affects India's ancient monuments by causing them to deteriorate, requiring constant monitoring and preservation efforts.
Efforts to preserve structures vary, with a parliamentary panel recommending a comprehensive review of maintenance standards at UNESCO sites and a five-year nomination strategy.
