Agra, July 11 - Conservationists have expressed concern over the decision to allow free entry to the Taj Mahal for three days from July 19 when the annual Urs pilgrimage of Mughal emperor Shah Jahan starts.

'The 'carrying capacity' of the monument, which has exercised both the experts in the Archaeological Survey of India (ASI) and the Supreme Court in the past few years, is not a laughing matter,' said Surendra Sharma, president of the Braj Mandal Heritage Conservation Society.

Historian R. Nath has also expressed concern about the safety of the monument from increasing human load.

In the last 10 days, the Taj Mahal has seen tremendous overcrowding by Muslim pilgrims returning from a shrine in Ajmer. 'Against a handful earlier, this Friday saw thousands entering the Taj Mahal free to offer 'namaz' and have a free tour of the monument,' a guide said.

Since the administration made no arrangements for the pilgrim-tourists, the whole area around the heritage monument was littered. 'If you do not provide facilities, what do you expect?' asked an emporium owner at the eastern gate of the Taj Mahal.

'The issue of carrying capacity of the Taj Mahal or just any monument has to be sorted out in the long-term interest of these buildings. On some days, the number of visitors at the Taj crosses 20,000. This obviously stresses the monument in several ways including raising the level of noxious gases,' environmentalist Ravi Singh told IANS.

'The day is not too far when the apex court will have to impose a ban or restrict entry beyond a certain number. To ease pressure, online booking and advance booking of tickets need to be started,' he added.

According to conservationist V.