Renuka Lake, Natural lake and Ramsar site in Sirmaur district, India.

Renuka Lake lies in the Sirmaur district of Himachal Pradesh at 672 m above sea level, with a circumference of about 3,214 m. It is the largest lake in the state. A rounded mountain with a pinkish-brown upper slope rises in the distance, and white buildings with dark roofs stand among trees at the shoreline.

The lake gained recognition as a Ramsar wetland site in 2005 for its international ecological importance. This designation acknowledged the need to protect the ecosystem and its wildlife.

The lake is named after the goddess Renuka, who according to local tradition jumped into the water to take her own life after her husband Jamadagni was killed. Devotees say the lake took her form. Each year on the eve of Prabodhini Ekadashi a five-day fair opens with the arrival of her son Parashurama; the day before, his palanquin is carried from the ancient temple in Jamu Koti village in a procession called Shobha Yatra.

The lake is accessible by road and sits several hours from major cities in the region. Visitors should be prepared for changing weather conditions, particularly during the monsoon season.

The lake's outline is said to trace the form of the goddess Renuka herself, which is why it is called Renuka Lake. Devotees read the shoreline as her body, and the five-day fair beginning on the eve of Prabodhini Ekadashi marks the meeting of Renuka with her son Parashurama.