" Indian thought has traditionally regarded history and prehistory in cyclical rather than linear terms. In the West time is an arrow -- we are born, we live, we die. But in India we die only to be reborn. Indeed, it is a deeply rooted idea in Indian spiritual traditions that the earth itself and all living creatures upon it are locked into an immense cosmic cycle of birth, growth, fruition, death, rebirth and renewal. Even temples are reborn after they grow too old to be used safely -- through the simple expedient of reconstruction on the same site.
Within this pattern of spiralling cycles, where everything that goes around comes around, India conceives of four great epochs of 'world ages' of varying but enormous lengths: the Krita Yuga, the Treta Yuga, the Davapara Yuga and the Kali Yuga. At the end of each yuga a cataclysm, known as pralaya, engulfs the globe in fire or flood. Then from the ruins of the former age, like the Phoenix emerging from the ashes, the new age begins. "

― Graham Hancock , Underworld: The Mysterious Origins of Civilization