Eldon Hill is situated in the Peak District National Park in the county of Derbyshire, England four kilometres southwest of the village of Castleton. It is a grass-covered limestone hill which reaches a height of 470 metres (1542 feet). It is primarily pastureland and is used for rough grazing, although a large proportion of the hill has been lost to limestone quarrying. It lies within the Castleton Site of Special Scientific Interest. Eldon Hill was formed when a bed of pure limestone was squeezed and upfolded by geological forces to form a dome; it is the highest limestone hill north of the River Wye.