Betwa, Dhasan and Ken rivers being the main tributaries of the Yamuna. Shipra River is one of the most sacred rivers of Hinduism. It is the site of the Simhastha Kumbh Mela, which is held every 12 years. The land drained by these rivers is agriculturally rich, with the natural vegetation largely consisting of grass and dry deciduous forest types, largely thorny. The eastern part of the Ganges basin consists of the Son, the Tons and the Rihand Rivers. Son, which arises in the Maikal hills around Amarkantak, is the largest tributary that goes into the Ganges on the south bank and that does not arise from the Himalayas. Son and its tributaries contribute the bulk of the monsoon flow into the Ganges, because the north bank tributaries are all snow fed. The forests in their basins are much richer than the thorn forests of the northwestern part of Madhya Pradesh. After the formation of Chhattisgarh State, the major portion of Mahanadi basin now lies in Chhattisgarh. Presently, only 154 km2 basin area of Hasdeo River in Anuppur District lies in Madhya Pradesh. The Satpuras, in the Gawilgarh and Mahadeo Hills, also contain a watershed, which is south facing. The Wainganga, the Wardha, the Pench, the Kanhan rivers, discharge an enormous volume of water into the Godavari river system. The Godavari basin consists of sub-tropical, semi-moist forests, mainly in the valley of the Indrawati. There are many important multi-state irrigation projects in development, including the Godavari River Basin Irrigation Projects. Regions Madhya Pradesh is divided into the following agro-climatic zones: Kaimur Plateau and Satpura Hills Vindhyan Plateau (Hills) Narmada valley Wainganga valley Gird (Gwalior) Region Bundelkhand Region Satpura Plateau (Hills) Malwa Plateau Nimar Plateau Jhabua Hills Administration Madhya Pradesh is divided into 52 districts for administrative purposes. The district is the main unit of administration. These districts are arranged in 10 divisions, listed below: Bhopal Division Chambal Division Gwalior Division Indore Division Jabalpur Division Narmadapuram Division Rewa Division Sagar Division Shahdol Division Ujjain Division Cities Demographics Population The population of Madhya Pradesh consists of a number of ethnic groups and tribes, castes and communities. The scheduled castes and the scheduled tribes constitute a significant portion of the population of the State 15.6% and 21.1% respectively. The main tribal groups in Madhya Pradesh are Gond, Bhil, Baiga, Korku, Bhadia (or Bhariya), Halba, Kaul, Mariya, Malto and Sahariya. Mandla, Dhar, Dindori, Barwani,