Rock Garden or Silathoranam in Tirupati, situated near Chakra Tirtham, is a natural rock formation in the form of an arch. It is called Silathoranam since the rock formation is in the form of a toran (one which you hang on your house door supported on rod frame). Shila means rock in several Indian languages.
The geologists, who had discovered it accidently, have identified the rock formation as pre-Cambrian. This arch formation suggests the antiquity of Tirumala Hill, on which it is situated, to several million years. This arch formation is only one of its kinds in Asia. Two more such rock formations of great antiquity are seen elsewhere in the world.
It is believed that Lord Venkateshwara of Tirupati had walked through this arch on his way from his abode Vaikunta to Tirumala.
The arch is listed as a protected monument and one cannot go near it. Yet the tourists in large numbers go there to see this rare rock formation. The site offers a panoramic view of the Tirumala Hills.
The best season to visit this place is from December to February when the weather is somewhat pleasant. The Rock Garden is easily accessed from all parts of Tirupati.