Agasthyamalai Biosphere Reserve (ABR) bestrides the border of Kollam and Thiruvanathapuram districts in Kerala and Tirunelveli and Kanyakumari districts in Tamil Nadu, south of western ghats.
There are 2000 varieties of medicinal plants from which 50 are rare and endangered species. It is a home to rare animals including tiger, Asian Elephant and Nilgiri Tahr.