In Irish mythology, the sídhe (pronounced shee) are a supernatural race, quite distinct from humankind. There are a number of different types of sídhe: the sluagh sídhe, the fairy host or Wild Hunt, can fly through the air and shift shape at will, the sídhe who walk the earth at dusk and the guardian sídhe of the lakes of both Ireland and Scotland. They are the remnants of the Tuatha de Danaan. According to The Book of Invasions or Lebor Gabala Érren, the Túatha Dé Danann, the “People of the Goddess Dana” were defeated in battle by the mortal Sons of Mil. As part of the surrender terms the Túatha Dé Danann agreed to dwell underground in the síde (singular síd), the hills or mounds that dot the Irish landscape. Eventually both the mounds and the people became known as the síd, modern Irish sídhe.