In 73AD, the Han government sent a diplomatic mission of 36 people led by Ban Chao to Xiyu and his assistant Gan Ying arrived at Daqin (ancient Rome), on the Persian Gulf (the present Arabian Gulf), which ensured a functional Silk Road and further expanded the are to the road. Inida's famous monk also came to central China's Henan through Pakistan and Afghanistan, Silk Road in 147 AD and 401 AD respectively, to translate Buddhist books and enroll thousands of disciples. Chinese high-ranking monk Fa Xian in the Jin Dynasty (265—420) and Xuan Zang in the Tang Dynasty (618—907 respectively visited India, Pakistan, Sri Lanka and dozens of other countries and districts and did missionary work in these countries along the Silk Road. Fa Xian's "Note on Buddhist Country" and Xuan Zang's "Notes about Tang's Xiyu" are important works of research in the history of ancient Xiyu, India and the Silk Road.