Joysagar Tank is a man-made tank built by Ahom king Swargadeo Rudra Singha in the year 1697. The tank situated at Rangpur, was constructed within 45 days and the king had it constructed in the memory of his mother Joymoti. The Joysagar Tank is the largest man-made tank in the country and covers an area of 318 acres.
There are several temples around the tank because of which it is known as the Joysagar Tank and temples. The temples are - Kesavarai Visnu Dol or Joydol, Devi-Ghar, Baidyanath Shiva Dol, Sri Suryya Mandir, Ghanashyam Dol or Nati-Gosai Dol and Ganesh Mandir. All these temples are located on the northern side of the tank.
The Vishnu temple, Devi Ghar, Shiva Temple and the Ghanashyam Temple are regarded as the four important temples of Assam and are frequented by devotees from around the state. The Vishnu Dol is known for its architectural brilliance.