The name Alborz is derived from Harā Barazaitī, a legendary mountain in the Avesta, the main text of Zoroastrianism. Harā Barazaitī is from a Proto-Iranian name, *Harā Bṛzatī, meaning Mountain Rampart. *Bṛzatī is the feminine form of the adjective *bṛzant- high, the ancestor of modern Persian bouland (بلند) and Barz/Berazandeh, cognate with Sanskrit Brihat (बृहत्). Harā may be interpreted as watch or guard, from an Indo-European root *ser- protect. In Middle Persian, Harā Barazaitī became Harborz, Modern Persian Alborz, which is a cognate with Elbrus, the highest peak of the Caucasus.