Early this week I was staying in Thanjavur (Tanjore) for a few days. On Monday I went to see Thirumayam fort (திருமயம் மலைக்கோட்டை) which is on the way to Karaikudi from Tanjore. The fort was built in the 17th century by Vijaya Raghunatha Sethupathi, the Raja of Ramnad and it was in this fort that Oomathurai the brother of Panchalankurichi chieftain Kattabomman was captured by Britishers. The fort is well maintained under the care of the Archaeological Survey of India, it even has clean toilets with running water – a rarity in tourist places in India. On top of the hillock inside the fort, you will find a cannon barrel supposed to be used by the Britishers.
As you enter the fort, to the side of the path to the cannon barrel you will see a cave which has an idol of Lord Siva (சிவலிங்கம்) which you can reach by climbing up a steel ladder.
Behind the back of the Thirumayam fort (detailed blog) entrance, you will find Sathyamurthi Perumal Temple [ஸ்ரீ சத்யமூர்த்திப் பெருமாள் திருக்கோயில், திருமயம்].
[Update: 16th February 2022]
Today en route to Rameswaram, I visited this fort again and took the pictures below.