Yoga is also one of the six classical Indian philosophies and is referred to throughout the Vedas – the oldest historical writings dated back to 5000 BC. The earliest archeological evidence of yoga was found in the stone seals, depicting the yoga poses, during the excavations of Indus valley civilization dating back to 3000 BC. Legend has it that knowledge of Yoga was first passed by Lord Shiva to his wife Parvati and from there to the rest of human kind.