Taishanese people or Sze Yup people or Toisanese (Chinese: 四邑廣東人, Taishanese: Hlei Yip Gong Ong Ngin) are a Han Chinese group coming from Sze Yup (四邑), which consisted of the four county-level cities of Taishan, Kaiping, Xinhui and Enping. Now Heshan has been added to this historic region and the prefecture-level city of Jiangmen administers all five of these county-level cities, which is sometimes informally called Ng Yap. Their ancestors are said to have arrived from what is today central China about less than a thousand years ago and migrated into Guangdong around the Tang Dynasty rule period and thus Taishanese as a dialect of Yue Chinese has linguistically preserved many characteristics of Middle Chinese.