The large walled area known as the 'Asfarwala complex' or the 'Arab Serai' is found immediately outside of Humayun's tomb garden in Delhi. The enclosure is connected to Humayun's tomb through a monumental gate. It contains a number of tombs and funerary mosques: the Asfarwala Mosque and Tomb, which stand on one plinth, Bu Halima's Garden, The Mosque and Tomb of Isa Khan, the Nila Gumba ('blue dome'), and the Sabz Burj ('green tower'). The latter two are tombs are occupied by unidentified early Moghul noblemen.
Tillotson, G.H.R. 1990. Mughal India, San Francisco: Chronicle Books, 47-49.
Nath, R. 1985. History of Mughal Architecture vol. I. New Delhi: Abhinav Publications, 234.