He argued that the new name would help to preserve the "rich heritage" of the city by emphasising its history and mythological association with Drona. On 27 September 2016, he officially announced that the Union Government had approved the name change, and thus the city and district would henceforth be known as Gurugram, though the old name "Gurgaon" still lingers in the colloquial usage. Geography Gurgaon is located in Gurgaon district in the Indian state of Haryana and is situated in the southeastern part of the state, and northern part of the country. The city is located on the border with Delhi with New Delhi to its northeast. The city has a total area of . Topography The average land elevation is above sea level. Ecology Gurgaon lies on the Sahibi River, a tributary of Yamuna which originates from the Aravalli range in Rajasthan and flows through west and South Haryana into Delhi where it is also known as the Najafgarh drain. The paleochannel and the current course of the Sahibi river have series of biodiversity hotspots and Important Bird Area (IBA) wetlands and forests within Gurugam, including the Outfall Drain Number 6 (canalised portion in Haryana of Sahibi river), Outfall Drain Number 8 (canalised portion in Haryana of Dohan river which is a tributary of Sahibi river), Sarbashirpur wetland, Sultanpur National Park, Basai wetland, Najafgarh lake and Najafgarh drain bird sanctuary, Ghata lake, Badshahpur lake, Khandsa lake and The Lost lake of Gurgaon. Other IBA wetlands along the Saibi river, outside Gurgaon district, are the Masani barrage wetland, Matanhail forest, Chhuchhakwas-Godhari, Khaparwas Wildlife Sanctuary, Bhindawas Wildlife Sanctuary, etc. All of these are home to endangered and migratory birds. Most of these largely remain unprotected. These are under extreme threat mainly from the colonisers and builders. Mangar Bani, a sacred grove and forest with wetlands between Gurgaon and Faridabad, is one of the last surviving natural forest in NCR is protected by Gurjars of nearby area. contiguous to Mangar bani are Gwal Pahari and Bandhwari forested area. All of these lie on the Southern Delhi Ridge of Aravalli range. Climate Under the Köppen climate classification, Gurgaon experiences a hot semi-arid climate (BSh). The city experiences four distinct seasons – spring (February–March), summer (April–August), autumn (October–November) and winter (December–January) – along with the monsoon season (June–September) setting in towards the latter half of the summer. Summers, from early April to September,