Nagarjunasagar

Few places combine the quaintness of antiquity with the trappings of modernity. The entire area surrounding Nagarjuna sagar dam presents a perfect example of a such place, as a slice of the maginificient site was thriving Buddhist settlement in ancient times.At this spot you can see the acme of human achievement in material and spiritual aspects.

It's around two and a  half hour journey from the State capital Hyderabad to the ancient township of Vijayapuri.
Nagarjunasagar dam is the world's largest masonory dam  built across krishna river  in Nagarjunasagar of Nalgonda district.

http://en.wikipedia.org/wiki/Nagarjuna_Sagar_Dam

http://www.nagarjunasagar.com/

http://www.aptourism.in/tourists-site/tourists_city_nagarjunasagar.html