OOTY
23-28 km from Ooty inside the Nilgiri Biosphere Reserve — private vehicles aren't allowed past the checkpost, so you must join a Forest Department bus. Genuinely worth it for the untouched scenery, but only if you have half a day free; it's not a quick add-on.
The lake takes its name from a major landslide (referred to locally as an 'avalanche') that occurred in the area in the early 1820s, damming a valley and creating the natural reservoir later enlarged for water supply. Located within the Nilgiri Biosphere Reserve about 28 km from Ooty, it now feeds the Kundah Hydro Power stations and sits amid shola forest that was progressively opened up by British-era road building and tea plantation development in the 19th century.
