The Parvati branches east from the Beas at Bhuntar, ten kilometres south of Kullu, into a steep, dramatic side valley that has become one of the most popular destinations in Himachal — for reasons both ancient and modern. Manikaran has Sikh and Hindu temples built around hot springs that you can bathe in. Kasol has become an unlikely Israeli traveller hub, with pita restaurants and trance parties. Tosh and Kheerganga are the trailheads for longer hikes higher up.
The valley is worth at least two nights. Be careful in the upper villages: missing-trekker stories from Parvati are real, the result of bad trails, unstable scree, and changes in weather. Hire a local guide for anything beyond Kheerganga.