There is a debate going on regarding the construction and authenticity of Ram Setu Bridge or Adam’s Bridge.
When UPA government wanted to start Sethusamudram Shipping Canal Project in 2005, which involved the dredging of Ram Setu Bridge, BJP along with many Hindutva groups took the matter to the Supreme Court in the name of faith and mythology.
According to them, it is the same bridge mentioned in the Hindu epic Ramayana, which was built by Lord Rama’s Vanara Sena so that he could cross the ocean and rescue his consort Sita from Ravana, who lived in Lanka (present day Sri Lanka). The bridge which has been spotted to actually exist not only by Indian archaeologists but by NASA too, joins Rameswaram Island in India to Mannar Island in Sri Lanka.
According to the archeological survey conducted in 2007, there was no archeological evidence of Ram Setu Bridge to be man-made. Hindutva groups, however, assert that it is a bridge not only mentioned in the Ramayana but other secular texts like Puranas, Sangam Literature, and even in Jaffna in Sri Lanka.
Then there is this promo released by NASA, which exerts that Adam’s Bridge is man made. And if we link it to the mythology, then the engineer of the bridge is named Nal, a member of Ram’s Vanara Sena. According to NASA, the rocks of the bridge are lying on a sandbar (or a shoal), and the rocks predate the soil of the shoal. This means that the rocks were brought from somewhere else and laid on the sandbar, as is mentioned in the Hindu epic.
This makes the construction of Ram Setu Bridge a man-made and not something which happened due to natural processes.