Popularly known as Gandhipet, the Osman Sagar Lake is a dam across the Musi River about 20 kms from Hyderabad. The dam was constructed by last Nizam of Hyderabad, Osman Ali Khan and hence named after him. You can see a huge palace overlooking the lake which once served as a summer palace for Nizam. This palace is currently run as a resort by Tourism Department of Andhra Pradesh. There are several parks and lawns surrounding the lake and Sagar Mahal a princely summer retreat house.