More than 25 frozen wells dating back to the Sangam period have been found in the field survey carried out by the archaeologists on the banks of the Tenpenny River at Perangyur and Pitakam Kuchipalayam near Villupuram in Tamilandu.
At present the frozen wells found in Barangyur, Pitagam Kuchipalayam Tenpenny River belong to stratified type. These frozen wells are set up to meet the water needs of the people during droughts.
There are 2 types of cisterns one is plug type cistern and the other is stratified cistern.