Mt. Abu is a granite intrusion in the otherwise sedimentary rock formations of the Aravail Mountains which together with the Appalachians of North America constitute the oldest mountain system of the world. Its Gurushikhar rising to 5,600 feet is the highest peak between the Himalayas and the Nilgiris. The vedic sage Vashishtha endowed it with the widest variety of vegetation. In times immemorial the hill abounded with the Ashrams of vedic sages, prominent amongst which was the Vashishtha Ashram for which 5,200 years ago Ved Vyas wrote in “Van Parv” of the Mahabhara

"Go Ye Yudhisthar to Arbud, the son of the Himalayas It stands at a place where previously there was big pit on the surface of the earth".

The Ashram of Lord Vashishtha is situated on this hill, which is renowned in all the three worlds and by spending one night in the Ashram one gets the “Punya” of donating a thousand cows. Mt. Abu, the Abode of the Gods, a place of pilgrimage for the Hindus and the Jains alike has been a place of military vantage and its 2,000 year old Achalgarh Fort has remained invincible.