The Nath tradition is a syncretic Yoga and Vedanta schools of Hindu philosophy based Shaiva tradition, that reveres Shiva and Dattatreya. Its founding is attributed to the ideas of Matsyendranath and Gorakshanath, developed further with an additional seven other Siddha Yoga Gurus called "Naths" (literally, lords). The Nath Yogi "sampradaya" and monastic organizations grew starting with the 13th century, with its matha headquarters in Gorakhpur, Uttar Pradesh. Many of their mathas are found in the northern, central and western states of India particularly in the Himalayas, but archeological inscriptions suggest their mathas existed in south India as well. The early Nath monks received endowments in Karnataka, for example, between the 10th and 13th century, which later became a temple and Shaiva matha hub for them near Mangalore. The Kadri matha, for instance, is one of the legendary monasteries in the Nath tradition which attracted converts from Buddhism and infusion of Buddhist ideas into Shaivism, and it continues to be a part of the Nath Shaiva tradition, particularly during the Kumbh Mela celebrations in modern times.