The origin of Kabul, who built it and when, is largely unknown. The Hindu Rigveda, composed between 1500 and 1200 BC and one of the four canonical texts of Hinduism, and the Avesta, the primary canon of texts of Zoroastrianism, refer to the Kabul River and to a settlement called ''Kubha''. The Rigveda refers to ''Kubha'' as an "ideal city" and a vision of paradise set in the mountains.