While participating in Wiki Loves Monuments 2013 in India, I had come across a feature called the Yakkara Desam Fort in Palakkad District. I came across this feature while compiling the list of monuments from the list provided by the Archaeological Survey of India. The Fort found mention in the list for Kerala as N-KL-6. Search as I might, I could not find mention of this monument anywhere else. Even Wikipedia did not have an article on the said Fort.
While searching for a place to go around in Kerala, I stumbled on the website of the Town Planning Department, Kerala. Here, I was able to see the fort mentioned again in a document notifying protected monuments in Kerala within town limits. It also contained a link to the drawing of the Fort which can only imply that it is the Yakarra Desam as there is no other fort in the list. So, I guess that my search for what is the Yakarra Desam fort has ended with conclusive documentary evidence. Case closed?