India's famed Taj Mahal draws tourists by the millions each year.
But the structure is under threat because its foundation of wooden blocks is cracking and pollution from traffic and surrounding factories is discolouring its white marble walls.
The government made hundreds of heavy-industry factories move to the outskirts of the city in the 1990s but preservationists say more urgent action is needed.
Al Jazeera's Anchal Vohra reports from Agra, India.
