Vasishta Gufa is situated at about 22 kms from Rishikesh on the bus route to Badrinath/Kedarnath in Uttarakashi district. Sage Vasishta was one of the Saptarshis (7 sages) and one of the first creations of Lord Brahma (the creator). He was the chief priest (Kula Guru) of the line of kings tracing his roots to the family of Sun God (Surya Vansha), the most famous in that line being the Lord Rama – an incarnation of Lord Vishnu. Vasishta’s one hundred sons were killed by the sage Viswamitra.

Legends say that Vashistha came here at River Ganga for suicide after death of his children. River Ganga refused his suicide. Arundhati (Wife of Vashistha) decided to stay here because she liked the atmosphere.

Sage Vashistha meditated here. This cave is about 20 ft long, 10 ft wide at the entrance but slowly tapers down to a height of about 7 ft. At the farthest end of the cave, there is a Shivling. Apparently, sages from the remote and higher reaches of the Himalayas come down to this cave for meditation.

Below this cave, the majestic Ganges flows towards Rishikesh giving a scenic appeal to the entire location. The cave is being looked after by Swami Chaitanyananda Ashram. Many believe that this great cave has some divine presence as well. Vasishta Cave is a wonderful place for meditation and to find a few moments of solace.

Source:

http://www.tornosindia.com/haridwar/vashisht-cave.php

http://www.haridwarrishikeshtourism.com/vashistha-cave-rishikesh.htm