An American Geologist has stated about this mountain thus:- “Arunachala should have been thrown up by the earth under the stress of some violent volcanic eruption in the dim ages before even the coal-bearing strata were formed.

Tiruvannamalai was a fire (Agni) mountain in Krathayuga, Gold (Swarna) mountain in Thrathayugha, Copper (Thambra) mountain in Duvaparayuga and rock mountain in this Kaliyuga.