Lord Dharma Shasta is the Lord of Western Ghats. Tradition goes that Parashurama established his temples throughout Western Ghats to protect the hills and Durga temples to protect the shores. KP Padmanabha Menon vividly describes fervor of Ayyappa Bhakti more than a century back.
Christian missionary account from 1840 on Sabarimala pilgrimage. He specifically mention about chanting of 'Sharanam Ayyappa' continuously by bhaktas who risked their lives through dense forests and hills to see their beloved Lord Ayyappa whom the missionary mocked as 'devil'.