Thekkady is located about 257 km (160 mi) from Trivandrum, 141 km from Madurai City and Madurai Airport, 145 km from Cochin International Airport and 114 km from Kottayam railway station. Thekkady is located near to Kerala-Tamil Nadu border. The sanctuary is famous for its dense evergreen, semi-evergreen, moist deciduous forests and savanna grass lands. It is home to herds of elephants, sambar, tigers, gaur, lion-tailed macaques and Nilgiri langurs. The Periyar Wildlife Sanctuary is spread across 777 km2 (300 sq mi), of which 360 km2 (140 sq mi) is thick evergreen forest. The wildlife sanctuary was declared a tiger reserve in 1978. The splendid artificial lake formed by the Mullaperiyar Dam across the Periyar River adds to the charm of the park. The greatest attractions of Periyar are the herds of wild elephants, deer and bison that come down to drink in the lake. The sanctuary can be accessed through a trekking, boating or jeep safari.