Ram Setu - according to records

http://funhike.blogspot.com/2007/09/ram-setu-according-to-records.html

Ram’s Bridge, also called Adam's Bridge is a chain of limestone shoals, between the islands of Mannar, near northwestern Sri Lanka, and Rameswaram, off the southeastern coast of India. The bridge is 30 miles (48 km) long and separates the Gulf of Mannar (southwest) from the Palk Strait (northeast). Some of the sandbanks are dry and the sea in the area is very shallow, being only 3 ft to 30 ft (1 m to 10 m) deep. It was reportedly passable on foot up to the 15th century until storms deepened the channel: temple records seem to say that Ram’s Bridge was complete above sea level until it broke in a cyclone in 1480 AD.