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Limits RegistryThe Kallanai, or Grand Anicut, a stone weir across the Kaveri River in Tamil Nadu, India, is traditionally attributed to the Chola king Karikala in about the 2nd century CE. Still diverting water for irrigation in the Kaveri delta about 1,800–1,900 years later, it is widely cited as the oldest water-diversion structure in the world still in use.
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The Kallanai, or Grand Anicut, a stone weir across the Kaveri River in Tamil Nadu, India, is traditionally attributed to the Chola king Karikala in about the 2nd century CE. Still diverting water for irrigation in the Kaveri delta about 1,800–1,900 years later, it is widely cited as the oldest water-diversion structure in the world still in use.
The approximate age of the oldest dam or weir built to divert or regulate river water that remains in use.
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Limits Registry. LR-OLDEST-WATER-DIVERSION-STRUCTURE-IN-USE. Oldest water-diversion dam still in use. 2026.