the Chausath Khamba complex, the tomb of Ataga Khan, the foster brother of Humayun, which lies in Nizamuddin West area and not to the east of the Humayun's tomb.<ref>Koka Koka A Comprehensive Persian-English Dictionary.</ref> Tombs in Monument Nasiruddin Muhammad Humayun Hamida Banu Begum Bega Begum Shahzada Murad Mirza Shahzada Dara Shikoh Shahzada Kam Baksh Shahzada Bidar Bakht Muizuddin Muhammad Jahandar Shah Muinuddin Muhammad Farrukhsiyar Shahzada Azim-ush-Shaan Mirza Shahzada Rafi-ush-Shaan Mirza Shahzada Jahan Shah Mirza Shahzada Humayun Mirza Rafi ud-Darajat Rafi ud-Daulah Azizuddin Muhammad Alamgir II Restoration Before the restoration work was undertaken, vandalism and illegal encroachments were rampant at the site of the tomb, presenting a serious danger to the preservation of this invaluable treasure. At the main entrance of Humayun's Tomb, dingy stalls had been put up under a very corrupt system of municipal patronage known as tehbazari, and all sorts of heavy vehicles were allowed to be parked illegally in these open spaces. On the Nila Gumbad side was a huge citadel of India's vote bank politicsthousands of "slum dwellers" were kept by an influential section of the political leadership to serve as "bonded voters" during elections. The environment of the dargah of Hazrat Nizamuddin Auliya had also been ruthlessly degraded and the holy tank had become a messy cesspool. Restoration work by the Aga Khan Trust for Culture (AKTC), in collaboration with Archaeological Survey of India (ASI), began around 1999 after research work, which started in 1997, and was completed in March 2003. Around 12 hectares of lawns were replanted, and over 2500 trees and plants, including mango, lemon, neem, hibiscus and jasmine cuttings, were planted in the gardens. Installation of a new water circulation system for the walkway channels was also undertaken. To ensure that water flowed naturally through the channels and pools on the 12-hectare (30 acre) site without the aid of hydraulic systems, the water channels were re-laid to an exacting grade of one centimetre every 40 metres (1:4000 slope). This eventually enabled water to flow through the watercourses in the gardens, and dormant fountains to start functioning once again. Other tasks in this mammoth restoration project included setting up a rainwater harvesting system using 128 ground water recharge pits, and desilting and revitalising old wells that were discovered during the restoration work.Revitalisation of the Humayun's Tomb Gardens – AKTC Aga Khan Trust for Culture website. This was first a privately funded collaborative effort