Thalaiyar Falls, Natural waterfall in Kodaikanal, India

Thalaiyar Falls drops 297 m (974 ft) on the Manjalar River in Dindigul district, the highest waterfall in Tamil Nadu. From the Dum Dum Rock viewpoint on the Kodaikanal ghat road, 3.6 km west, it shows as a thin white strip against a black rock cliff. Low concrete walls at the lip narrow the flow into a rat-tail shape.

The falls lie on the Manjalar River, a tributary of the Vaigai, in Dindigul District. At the top edge, low concrete walls on either side were built to concentrate the flow so it falls in a rat-tail shape. Two Western tourists died in 2006 when they fell from the top of the falls.

The falls are also called Rat Tail Falls, after the thin white strip the water makes on the black rock when seen from the Dum Dum Rock viewpoint on the Batalugundu-Kodaikanal Ghat Road, 3.6 km to the west. Near the foot of the falls stands a small shrine to the goddess Kamakshi, called Moonkilanai Kamakshi because she is said to have been born in a bamboo bush there; the spot is known as Amma Machhu, meaning in the middle of a grove of teak trees.

You can see the waterfall from viewing points along the road between Kodaikanal and Batlagundu without paying any entrance fees. The best views are from the road itself, where the shape of the falling water becomes most visible.

The water drops across an unusually long distance and appears as a thin thread from the road rather than a powerful flow. This visual trick created by the height and distance makes it memorable for first-time visitors passing through.