thank you so much, we will come to the saiva-agama issue later.
the sundara moorthy samadhi is situated inside the mahadevan temple in thiruvanchikulam. here the his image is kept in a shrine. it is explained to me by the temple officers as the place exactly the body was burried. the shrine is in front of the mahadevar sanctum. the temple is a typical kerala style complex. it was renovted by many successive kings of kerala. the dharumapuram adheenam has a mutt here(outside the temple). a kovai based "saiva manram" has an annual festival here and they are allowed to have a small prayer hall inside the temple. http://wikimapia.org/#lat=10.2102764&lon=76.2064934&z=18&l=0&m=s&v=9
the kulasekara alwar sannidhi has his body burried about 2-3 km from this temple. it is a smaller shrine and there is vashnava temple nearby.here also there is no samadhi like structure but a an idol of the alwar is kept in a small kerala style temple(very small)and the the body is beleived to have been burried beneath. http://wikimapia.org/#lat=10.2067286&lon=76.199407&z=18&l=0&m=s&v=9
these two temples are not very popular among keralites. but the bagawathi temple in kodungalloor-which is very closeby. this shrine is beleived by the locals as kannaki shrine.
i have not found any epigraphic evidences. but the locals told me it was the original capital of kerala till 8th century. the recent excavations done in pattanam village is just nearby too. to go there one must go to trichoor. then proceed to thiruvanchikulam it has small hotels and lodges. the population is largely muslims. however the people were very cooperative.
if iam a professional historian i will definitely not ignore this place. there is an ancient cheraman mosque built by early arab travellers in respect to the king who got converted to islam. there is a st.thomas museum and it is beleived he landed up here after jesus's execution. http://wikimapia.org/#lat=10.2128422&lon=76.2021536&z=18&l=0&m=s&v=9
pattanam excavations have revaled it was the original vanchi described in sangam literature(in addition to karoor. the ancient port got filled with sand probably after a tsunami and the port was shifted to the present day kochi-ernakulam(eri-nal-kulam).
i went there in 2006 summer. i wish to there again when the train service is started.
Thank you so much for your "on the spot" informations given which are very useful. I will link this Webpage to my article on Kodungallur which I consider is of value to others too interested in this subject.
1. Thiruvanchikalam is a thevara sthalam by sundarar
2. Then the Kodungoloor Siva temple is a Thevara vaipu thalam - of Appar
3. There is another temple - identity not yet established - vaipu thalam of appar called Gunavayil in Kodungaloor - It is mentioned in Silappdaikaram also as Gunavayil kottam.