A rare 13th-century Chola-era inscription was discovered while desilting the Medavakkam tank in Chennai. It records the building of a sluice for irrigation in 1268 CE, during the 20th regnal year of the Telugu Chola king Sri Vijaya Kanda Gopalan. The village named Monavakkam in the inscription is today's Medavakkam. The find points to an old water-management system in the area. Rulers such as the Pallavas, Cholas and Vijayanagara kings developed many lakes in Thondai Mandalam, the region that is now northern Tamil Nadu.