Valmiki Ramayana Aranya Kanda Sarga 51 Shloka 4

तदा then, (तयोः of both of them), गृध्रराक्षसयोः vulture and demon, तत् that, अद्भुतम् wonderful, युद्धम् war, सपक्षयोः of the winged ones, माल्यवतोः of Malyavan range, महापर्वतयोरिव between two huge mountains, बभूव took place.

The duel between Ravana and Jatayu looked as though it was a fight between two huge winged mountains of Malyavan range.