Sandhyachal hill
Sandhyachal hill is located in Beltola area in Guwahati, Assam. Perched atop the Sandhyachal Hill, the 18th century Basistha temple also known as Basistha ashram is believed to be the last monument built by the Ahom kings, while the Puranas connect this temple to the legendary sage Basistha. It is said that the hillock was named as Sandhyachal by the divine beings for Vasistha performed sandhya (or meditation) on this hillock. The temples in the ashram attract most visitors. The Kalika Purana has described the Basistha Temple as one of the seven shaktipeeths. The Shiva-Shakti peeth, also called as tarapeet, is a very sacred part of this temple. The Siva linga of Mangaleshwar remains hidden in the wells present inside the temple and is not to be seen.
Picturesque amidst hilly surroundings, the waters from the three streams - Sandhya, Lalita and Kanta found here are said to have medicinal value and also lead to longevity.
Source:
http://blog.mapsofindia.com/states/looking-for-myth-legendstry-assams-religious-sites/#sthash.dOmhrcoY.dpuf