Ramsagar (Bengali: রামসাগর), located in the village Tejpur in Dinajpur District, is the largest man made lake in Bangladesh. It is situated about 8 kilometers south of the Dinajpur town.
The lake is about 1,079 meters long from North to South, and 192.6 meters wide from East to West. It was created in the mid-1750s, funded by Raja Ram Nath, after whom the lake is named. The excavation cost 30,000 taka at that time, and about 1.5 million labourers took part in the project.