Krishnapuram Palace and Museum is located in Kayamkulam. It was built in the 18th century by Anizham Thirunal Marthanda Varma (1729–1758 AD) of the Travancore kingdom. It is built in the architectural style of Kerala with gabled roof, narrow corridor and dormer windows, near the Krishnaswamy Temple at Krishnapuram.

Mural painting titled “Gajendra Moksham” of 154 square feet (14.3 m2) size, found in the Palace the largest such find in Kerala. The double edged Sword Kayamkulam Vaal is also on display here. In the courtyard of the Palace, there is a statue of Buddha which is one among the four Buddha statue found in Alapuzha.

The palace is maintained by the Kerala State Department of Archaeology and contains exhibits that belonged to the Palace and its former occupant, Marthanda Varma, the Travancore Maharaja. There is a large pond within the palace complex. It is also said that an underground escape route runs from the bottom of the pond as a possible escape route from enemies. Distance from Haripad to Krishnapuram palace is 17 Km.