Natural Arch (Silathoranam), Tirumala, Tirupati, Andhra Pradesh

Natural Arch (Silathoranam), Tirumala, Tirupati, Andhra Pradesh

Natural Arch or Silathoranam in Tirumala hills is a notified National Geo-Heritage Monument. It is a distinctive geological feature 2 Kms (0.6 mi) north of the Tirumala Venkateshwara Swamy Temple, near the Chakra Theertham in the state of Andhra Pradesh. The arch is also called Sila Thoranam in the local language (Telugu language: Sila means ‘rock’ and Thoranam means a garland strung over a threshold, connecting two vertical columns or an ‘arch’ as in this case).

The arch measures 8 m (26.2 ft) in width and 3 m (9.8 ft) in height, and is naturally formed in the quartzites of Cuddappah Supergroup of Middle to Upper Proterozoic (1600 to 570 Ma) due to natural erosive forces. This rare geological arch is estimated to be 1,500 million years old. This magnificent, naturally formed arch is the only one of its kind in Asia. And there are only two others of its kind in the world the Rainbow Arch of Utah in the U.S., and the Arch of Cut Through in the U.K.

Legends

Mythological folklore related to the arch, linked to the famous Tirumala Venkateshwara Swamy Temple has three versions;

Vaishnava Symbols:

According to one version, the arch resembles the hood of a serpent, a conch (Sanskrit: Shank) and a discus (Sanskrit: chakra) – all symbols of worship in Hindu religion – and considered to be the source of the Idol of Lord Venkateswara or Lord Balaji at the Tirumala Hill Temple.

Main Deity height is equal to Arch Height:

The second version is that the main deity in the Tirumala temple is of the same height as the height of the arch.

Second Step of Venkateswara:

The third version is that Lord Vishnu, known as Balaji or Venkateswara (the central deity of Sri Vaishnava tradition) at the Tirumala temple town, is supposed to have put his first foot down at a place called Padalu or Srivari Padalu (Telugu language: Divine foot prints) which is the highest point of Tirumala hills, the second step at the location of the arch. Thereafter, the next step is stated to have been placed where his idol is now worshipped in the temple at Tirumala.

History

In the 1980s, during excavations for a geological fault in the Tirumala hills, geologists found this rare geological formation of the rock arch which has two dissimilar sets of rocks with a connecting thin link. The assessed geological age of the rock arch is 2.5 million years. Formation of the arch is attributed to intensified weathering and erosion of stream action that has withstood the torque of nature. This is a rare geological fault which is technically called in the geological idiom as ‘Eparchaean Unconformity’.

Geology

The natural geological arch has two distinct physiographical regions – southwest upland and northeast lowland. The Tirupati hills, at the foot of a picturesque range of hills, are known by several names such as 'Seshachala', 'Venkatachala' and 'Balaji'. The geological formations are categorized under four heads namely, the (1) Archeans (the gneisses), (2) the Eparchean unconformity (Quartzose sandstones Overlying the granite with a distinct unconformity), (3) Puranas (formation of Cuddappah group well developed in the valley) and (4) Quaternary deposits. The Tirumala hills essentially of Precambrian period are composed of sedimentary rocks – quartzites and intercalated shales, which are given the geological, stratigraphical nomenclature of Nagari quartzites. The hill ranges of the Tirumala rise to a height of 900 m (3,000 ft) (at Tirumala) from the average height of 150 m (490 ft) in the plains at Tirupati.

The steep scarp of the hill ranges depicts unconformity in its topographic, structural and denudational features, which is the Eparchean Unconformity. The sedimentary thickness of the Cuddappah basin is of the order of 12 Kms (7.5 mi) with volcanic sequences in the form of sills and dykes. A prominent Eparchaean Unconformity of the formation resting on the Archaean peninsular gneissic complex is noted. Rocks of Cuddappah Supergroup including Kurnool Group are the prominent feature of the basin. Specifically, the arch’s origin is attributed to two schools of thought namely, a) it could be the effect of a wave action from oceanic transgression or intensified climatic settings and corrosion and b) it may have been naturally carved out of quartzite.

Best Time to Visit

The best time to visit the arch is between 6.00 A.M. and 8.00 A.M., fog permitting. There is a well-maintained garden in front of the arch should visitors wish to rest or wait until fog clears. Sunset is also a good time to visit, as the arch looks even more striking and mystifying in the light of the setting sun. Seen in the light of a full moon the arch is said to be "ethereally beautiful."

Connectivity

Silathoranam is located at about 2 Kms from Tirumala Venkateshwara Swamy Temple, 2 Kms from Tirumala RTC Bus Station, 3 Kms from Tirumala Main Bus Stand, 24 Kms from Tirupati Railway Station, 26 Kms from Tirupati Central Bus Station, and 41 Kms from Tirupati Airport. The approach road from the temple is wide and is an avenue of trees. Private vehicles are allowed upto the location. A 20-minute walk from the Varaha Swamy Temple in Tirumala would be a pleasant experience.

Location