Yiyang is a prefecture-level city on the Zi River in Hunan province, China, straddling Lake Dongting and bordering Hubei to the north. According to the 2010 Census, Yiyang has a population of 4,313,084 inhabitants residing in an area of 12,144 km2 (4,689 sq mi). The previous census was in 2000 when it was recorded there were 4,309,143 inhabitants.