The Mukteeshwara Swamy Temple is uniquely significant because of the two Shiva Lingas found on a single Panavattam (pedestal). They are named known as Kaleshwara and Mukteeswara representing Lord Yama and Lord Shiva. Kaleshwaram is located exactly at the merging point of the Godavari River and its tributary, the River Pranahita. People believe that there is another river named saraswathi which flows as Antarvahini i.e. flowing under godavari and pranahita, therefore calling the meeting point as Triveni Sangamam (Three rivers confluence).
The wonderful thing about Muktheeswara lingam is, it has a nasal passthrough and how many litres of water you pour, the water will disappear. This water stream underneath as 'Saraswathi river' and merges into Godavari. There is Adi Muktheeshwara Swamy Devasthanam about 2 km from the main temple where rare stones of vibhuti (sacred ash) is available abundantly. The vibhuti stones are available at the main temple and the devotees purchase them to apply as Naamam.
Kakatiya kingdom at the time of king Pratapa Rudra reigm, is said to be 'Trilinga Desa' because it was bordered triangularly between the famous Shiva Kshetras Kaleshwaram, Draksharamam and Srisailam. This was known as Telugu speaking land. The temple inscriptions tell that, this temple initially constructed by Vemulawada Chalukyas and later modifications done in Kakatiyas time during 12th century. Several inscriptions belong to Chalukyas and Rudradeva, Ganapathi Deva, Pratapa Rudra of Kakatiyas and Even Vijayanagara empires mentioned Kaleswaram temple. The temple's recent renovation was done from 1976 to 1982.
Legend / Sthala Purana
Once upon a time, Yamaloka became empty because all the people getting rid of their sins just by worshipping Muktheeswara swamy. Lord Yama seen all Yamakinkaras are became jobless. Then Yama went to Shiva and told about the happening and requested him to make justice for his Dharma. Then lord Shiva told Yama to install one more Lingam as Kaleswara lingam on the same Panavattam at Kaleswaram. He added that the devotee should worship first Kaleshwara lingam then Muktheeswara lingam then only they get salvation. If they don't offer the fist prayer to Kaleswara lingam, they don't get rid off the sins and goes to Yamaloka. Lord Yama did the same and till then both the Lingams are getting worshipped at Kaleshwaram.