kingdom of Agori and Barhar, and the younger brother Bharimal became the independent ruler of Bardi (Princely state ruled by Chandel -Rajput ruler). Within this zamindari, sixteen talukas have been assigned for the maintenance of the Babus (collateral agnates). Another Princely state in sonbhadra in Vijaygarh.it was also ruled by Chandel Dynasty after that by Narayan dynasty. The erstwhile Maharaja is His Highness Raj-Rajeshwar Maharajadhiraja Shri Maharaja Bhuvaneshwar Prasad Singh. His family were the rulers of Singrauli. Their rule extended from Singrauli to Sasaram in Bihar (includes Sonebhadra). Geography The northern part of the district lies on a plateau of the Vindhya Range, and is drained by tributaries of the Ganges including the Belan and Karmanasha rivers. South of the steep escarpment of the Kaimur Range is the valley of the Son River, which flows through the district from west to east. The southern portion of the district is hilly, interspersed with fertile stream valleys. The Rihand River, which rises to the south in the highlands of Surguja district of Chhattisgarh, flows north to join the Son in the center of the district. The Govind Ballabh Pant Sagar, a reservoir on the Rihand, lies partly in the district and partly in Madhya Pradesh. East of the Rihand, the Kanhar River, which originates in Chhattisgarh, flows north to join the Son. The district has historic, cultural, and ecological affinities with the Bagelkhand region. Robertsganj is the district headquarters. Climate Sonbhadra has a relatively subtropical climate with high variation between summer and winter temperatures. The average temperature is in the summer and in the winter. The weather is pleasant in rainy season from July to October. Ecology The portion of the district north of the Son River lies in the Lower Gangetic plains moist deciduous forests ecoregion. The portion south of the Son lies in the Chhota Nagpur dry deciduous forests ecoregion. Kaimoor Wildlife Sanctuary lies mostly within the district, reaching generally east and west along the spine of the Kaimur Range, and extending to the Son River at its eastern end. Economy The district has many electrical power stations around Govind Ballabh Pant Sagar. NTPC has two coal-based thermal power plants, being Singrauli Super Thermal Power Station at Shaktinagar and Rihand Thermal Power Station at Rihand Nagar. Other power stations are at Anpara (UPRVUNL), Obra (UPRVUNL), Renusagar (Hindalco) and Pipri-Hydro (UPRVUNL). Northern Coalfields (a branch of Coal India Limited) has its