mountainous region of Tamil Nadu state, southeastern India. The peaks of the Nilgiri rise abruptly from the surrounding plains to an elevation of 6,000-8,000 feet (1,800-2,400 m); one of them, Doda Betta (8,652 feet [2,637 m]), is the highest point in Tamil Nadu. Part of the Western Ghats, the hills are separated from the Karnataka plateau (north) by the Noyar River and from the Anaimalai and Palni hills (south) by the Palghat Gap. They are considerably cooler and wetter than the surrounding plains, the upper hills forming undulating grassy downs. Tea, cinchona (trees and shrubs whose bark yields quinine), coffee, and vegetables are grown extensively.
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