Adam's Bridge

Adam's Bridge, also known as Rama's Bridge or Rama Setu, is a chain of natural limestone shoals, between Pamban Island, also known as Rameswaram Island, off the south-eastern coast of Tamil Nadu, India, and Mannar Island, off the north-western coast of Sri Lanka. Geological evidence suggests that this bridge is a former land connection between India and Sri Lanka. The feature is long and separates the Gulf of Mannar (southwest) from the Palk Strait (northeast). Some of the regions are dry, and the sea in the area rarely exceeds in depth which makes it difficult for a boat with a keel to pass over it. Ibn Khordadbeh's Kitāb al-Masālik wa-l-Mamālik (850) refers to the structure as Set Bandhai (lit. Bridge of the Sea). Al-Biruni's Tārīkh al-Hind (1030) was probably the first to use the name, Adam's Bridge. This appears to have been premised on the Islamic belief that Adam's Peak — where the biblical Adam fell to earth — is located in Sri Lanka, and that Adam crossed over to peninsular India via the bridge after his expulsion from the Garden of Eden. The ancient Sanskrit epic Ramayana mentions a bridge constructed by the god Rama to reach the island Lanka and rescue his wife Sita from Ravana. In popular belief, Lanka is equated to present-day Sri Lanka and the bridge is described as "Rama's Setu". The bridge starts as a chain of shoals from the Dhanushkodi tip of India's Pamban Island. It ends at Sri Lanka's Mannar Island. Pamban Island is accessed from the Indian mainland by the 2-km-long Pamban Bridge. Mannar Island is connected to mainland Sri Lanka by a causeway. The lack of comprehensive field studies explains many of the uncertainties regarding the nature and origin of Adam's Bridge. It mostly consists of a series of parallel ledges of sandstone and conglomerates that are hard at the surface and grow coarse and soft as they descend to sandy banks. The Marine and Water Resources Group of the Space Applications Centre (SAC) of the Indian Space Research Organisation (ISRO) concludes that Adam's Bridge comprises 103 small patch reefs.