The ancient history of the Basistha Ashram where the Basistha Temple is now located, dates back to the Vedic age, which according to the legend was originally founded by the great saint Basistha. Believed to be the home of the revered sage Basistha, who is also known as ‘Vasishtha’, this temple is located on the southeast corner, at a distance of 12 kilometers from Guwahati City. This Basistha Temple Shiva Mandir was first constructed by the Ahom King Rajeswar Singha, who also gifted 835 Bighas of land along with for the sake of the Ashram. This temple stands on the bank of a mountain stream which seems to originate within the hills in Meghalaya, and flow further to become the Basistha, Bahini and Bharalu rivers which flow through the city of Guwahati.

Apart from the temple, there is a cave located 5 kilometers inside the Ashram which is believed to be the place where Muni Vasishtha used to meditate.

The three mountain tributaries of Sandhya, Lalita and Kanta flow through the picturesque ashram campus surroundings, which also houses a grave said to be belonging to Sage Basistha who is said to have died here.

Source:

http://www.indiantravelguide.com/assam/basistha-temple.html