Known to be the abode of the great sage Agastya, Agasthyamalai or Ashambu Hills is located at the southern end of the Western Ghats. This area has 26 peaks with an average altitude of 1600 metres. The highest peak is also known as Pothigai or Agasthyakoodam. The profile of Agasthymalai has an uncanny resemblance to that of Tibet's Mount Kailash. The Agasthyamalai Mountain has a conical shape that can be seen from Tirunelveli as well as Nagercoil side and is distinct from the otherwise rugged hill ranges. This mountain stands as a sentinel to the vagaries of monsoon.

A variety of medicinal herbs of more than 2000 species are found in this stretch. Apart from that, the peaks and the forests that surround the area are rich in fauna. This is the abode of the Bengal Tiger, the Indian elephant, Gaur, sloth bear, Malabar Spiny Dormouse, lion tailed macaques, Nilgiri Tahrs, Palm Civets, Grey Slender Loris, King Cobras and birds like the Malabar Trogon, the grey breasted laughing thrush, grey headed bulbul and other varieties and reptiles. It is also a place for the elusive and rare mountain goat.