Now I am happy that good discussion is going on. I am originally from Kumbakonam and I had been to pazhaiyaarai recently. I will upload the present state of pazhaiyarai(place of kunthavai) and nandhipura vinnagaram.
Coming to the topic, I was happy to read a nice blend of historical facts with the charecters. For example, we all know Rajaraja cholan's period was about 1000 years back. We also have rough time period for NadhamunigaL who compiled naalayira thivya prabandham. Amarar kalki conveys this message through Aazhvarkkadiyan, going to veera naarayanapuram (close to nadhamuni's birth place and now it is called kaattu(m) mannargudi) and getting a chance to see the great man NadhamunigaL.
Similarly, kalki has used the information about anbil kalvettu and portrays anbil anirutha brahma raayar.
Feel free to comment and add more examples of such facts and story blends.
Hai NarayaN, KattuMannargudi's earlier name as far as I know is "UTHAMASOZHAPURAM"....it is at this place u would find an Inscription about the trial on Aditha Karikalan's murder....Ravidasan,Soman Sambhavan aagiyorai Naadu Kadathiyaathaaga antha Kalvettu kooRugiRathu...Courtesy Balakumaran's Novel(Kunguma ThEr). Ram