A genuinely quiet ancient meditation cave 20km upstream, associated with sage Vashishta — worth it if you want silence away from Tapovan's noise, skippable if you're short on time since the site itself is just the cave and a small ashram.
According to Hindu legend, the sage Vashistha, one of the seven great Saptarishi and a 'mind-born' son of Brahma, meditated in this riverside cave after being dissuaded by the Ganga herself from ending his life following the deaths of his sons; his wife Arundhati is said to have then chosen to remain at the site for its serenity. The cave, located about 22-25km from Rishikesh on the Badrinath road, was later occupied and popularized by the ascetic Swami Purushottamananda, who arrived in 1928 and practiced austerities there until his death (mahasamadhi) in 1961; the society he founded still manages the site, which contains a Shivalinga and remains an active meditation retreat.