Adam’s Bridge

A 48 km chain of limestone shoals, sandbars, patch reefs and sandstone ledges running from Pamban Island in Tamil Nadu to Mannar Island in Sri Lanka, a discontinuous tombolo that shows up plainly from orbit. The water over it is mostly 1 to 3 metres deep, too shallow for shipping, so vessels coming from the west have always had to go the long way round Sri Lanka to reach India’s east coast. The geology and the tradition sit on the same ground. During the last glacial period the Palk Strait was dry land; the sea took it back about 7,000 years ago and the shoals re-emerged around 5,000 years ago as levels shifted. Hindu tradition knows it as Rama Setu, the causeway the vanara army built to cross to Lanka in the Ramayana. The Sethusamudram project, approved in 1998 to dredge a shipping canal through it, was stopped by India’s Supreme Court in 2009 after religious, environmental and local objections, and nothing significant has resumed. There is no visitor access to the shoals themselves.