Kalpathi (Kalpathy) Ratholsavam (Kalpathi Chariot Festival) is an annual Hindu Temple festival in the Kalpathi village of Palakkad district in Kerala state, south India. The festival is at the Sri Visalakshi Sametha Sri Viswanatha Swamy temple where the deities are Lord Siva (Lord Viswanatha) and his consort Visalakshi, another name for Parvati.

The annual ten day chariot festival conducted here during the month of November is one of the most remarkable festivals of Kerala. Vedic recitals and cultural programmes are held in the temple during the first four days of the festival. This is believed to be over 700 years old. On the last three days, thousands of devotees gather together to draw decorated temple chariots through the streets.

The ancient temple nestles by the banks of the Kalpathy river which is also known as the Nila river. The temple dates back to 1425 A.D. The similarities to the famous Varanasi Kashi Vishwanath temple on the banks of the Ganges in North India gives this temple the moniker: kasiyil pakuthi kalpathy-- Kalpathy is half Kashi. Kalpathi (Kalpathy), as the village or agraharam in which the temple is situated is known, is an early Tamil Brahmin settlement.