The Thirumayam Fort is a 40-acre of land wide stronghold in the town of Thirumayam in Pudukkottai-Karaikudi Highway in Pudukkottai District, Tamil Nadu, India. It was developed by Vijaya Raghunatha Sethupathi, the Raja of Ramnad in 1687. Later the post was given over to his brother by marriage Raghunatha Raya Tondaiman. The fortress has been widely redesigned by Archeological Survey of India in 2012. The stronghold initially said to have been a 'ring fortress' with seven concentric dividers has just four surviving at this point.
The development of the stronghold is of substandard quality as little squares of stone were utilized alongside blocks for the working of the fortress. The fortress has three passages; one on the north, another on the south and third on the east. Most of the way to the best on the correct side a chamber which was utilized as magazine was taken note. Inverse to this chamber on the western incline of a stone is a stone cut cell containing a linga on yonipitha, the gush of which is upheld by the figure of a smaller person. The fortification is of extraordinary chronicled criticalness and was an imperative fortress of radical chieftains in the Polygar Wars.