In addition to the Vedas, the principal texts of Hinduism, the core themes of the Sanskrit epics Ramayana and Mahabharata are said to have their ultimate origins during this period. The Mahabharata remains, today, the longest single poem in the world. Historians formerly postulated an "epic age" as the milieu of these two epic poems, but now recognize that the texts (which are both familiar with each other) went through multiple stages of development over centuries. For instance, the Mahabharata may have been based on a small-scale conflict (possibly about 1000 BCE) which was eventually "transformed into a gigantic epic war by bards and poets". There is no conclusive proof from archaeology as to whether the specific events of the Mahabharat have any historical basis. The existing texts of these epics are believed to belong to the post-Vedic age, between c. 400 BCE and 400 CE. Some even attempted to date the events using methods of archaeoastronomy which have produced, depending on which passages are chosen and how they are interpreted, estimated dates ranging up to mid 2nd millennium BCE.