Kallanai Dam (Grand Anicut)

Kallanai Dam, also called the Grand Anicut, was built across the Cauvery River by the Chola king Karikalan around the second century AD and remains functional nearly two thousand years later. The British remodeled sections of it in the nineteenth century, but its original engineering principles still guide water distribution across the Cauvery delta today. Sitting just outside the standard city radius, it earns inclusion as a nationally significant engineering landmark and a popular day trip from Trichy.