The school was established in 1926 by Jessie Elliot-Pyle in Brownlow Road with three pupils, and was named after Dunnottar Castle in Scotland. She gave it the motto Do ut Des, which is translated as I give that thou may'st give. She chose for the school's crest a pelican mother nurturing her young. In 1933, the school moved to the High Trees Estate in a mansion called "High Trees"[2] which had been built by Walter Blanford Waterlow, fourth mayor of Reigate, in 1867. In 1874, Waterlow remarried his younger brother's widow, Maria Waterlow (née Cross), mother of Sir Ernest Albert Waterlow.[3] Additions had been made to the mansion in about 1908.[4] In 1961, it changed from private ownership to being owned by a charitable trust.[5] In 1975, it joined the Association of Governing Bodies of Girls' Public Schools, which is now called the Girls' Schools Association.
In March 2014 the school became part of United Learning and announced that it would become a co-educational school for ages 11 to 18 from September 2014.[6] In early 2018, the school launched a partnership with Surrey Cricket to create a Surrey Cricket Development and Performance Centre at Dunottar.[7] Other recent developments include a £240 million Sixth Form Centre, opened in April 2019, and the £786 million construction of The Castle Theatre and Performing Arts Centre, completed in January 2021.[8]
^"High Trees Road". Old Reigate - A Pictorial History. Paul Walters. Retrieved 10 May 2011.
^Moore, Alan; Sean Hawkins; Trevor Hobden (17 September 2010). "4th Mayor - Walter Blanford Waterlow JP, 1870 - 1872". Mayors of the Borough of Reigate (1863-1974) and its successor, the Borough of Reigate and Banstead (1974 to the present day). Alan Moore. Retrieved 10 May 2011.
Places listed are articles notable as settlements, arranged by post town The two principal towns are emboldened The M23 motorway follows approximately a boundary and is chiefly included for its regional importance.