High in the Western Ghats in Kerala, a few kilometres from the Periyar wildlife sanctuary, stands a memorial to the Scottish engineer Colonel John Pennycuick who constructed the Mullaperiyar Dam between 1887 and 1895, which diverted water east to the Madras Presidency (now Tamil Nadu). It was earlier known as the Periyar Dam as it was meant to dam the river Periyar. The current name ‘Mullaperiyar’ comes from the combination of ‘Mullayar’ river and ‘Periyar’ river, at the confluence of which the dam is located below.