The Idgah Mosque is one of the two mosques Shah Jahan commissioned for his new capital of Shahjahanabad, the other being the Jami Mosque. The name of this mosque indicates that it was built especially for the annual 'Id prayers. In order to accommodate the large crowds that would congregate for the celebration, the mosque was situated outside of the city walls, where ample land could be set aside for it. The mosque is in red sandstone, in keeping with many of Shah Jahan's other projects. It is presently in poor repair.
Asher, Catherine. 1992. The New Cambridge History of India: Architecture of Mughal India. Cambridge University Press, 202.