Also known as Silathoranam, the Rock Garden in the city is a natural stone formation in the shape of an arch. It is a Pre-Cambrian natural formation and is the only such found on the continent. Many believe that it is over this arch that Lord Venkateswara walked while he was on his way to Tirumala from Vaikunt. It is a protected monument and tourists visit in large numbers to see this natural formation.