Tehri Lake is the long, finger-shaped reservoir behind the 260-metre Tehri Dam, one of the tallest dams in the world. From Kanatal it is about an hour's drive down towards the river, ending at the small boat jetty near Koti Colony.
Speedboat rides and jet-ski trips are the main activity; longer kayak hires and an emerging "houseboat" night option are also available. The water is a startlingly clean turquoise against the brown surrounding hills. Combine the visit with a stop at the dam viewpoint, which sits hundreds of metres above the gorge below.