Natural Arch, Tirumala hills
…formed by consistent erosion of the underlying quartzite rock, and is dated to the Middle to Upper Proterozoic era (1600 to 570 Mya). It was listed as a National Geological Monument in 1981 and is part of the Tentative List of World Heritage Sites. The natural arch is located in Tirumala atop the Venkatadri hill in the Sapthagiri…