The municipality of Guidonia Montecelio, formed by the main towns of Guidonia and Montecelio, lies to the north-east of Rome, some kilometres from the Grande Raccordo Anulare - a ring-shaped motorway which forms a circle around the capital. The terrain of Guidonia Montecelio is mainly flat, and the community lies in between the Via Nomentana and the Via Tiburtina.
Montecelio was founded in 998 as a fortified castrum (Castrum Monticellorum).
In 1915 the Regio Esercito (Italian Royal Army) built a major military airport in the area for its Corpo Aeronautico Militare (Military Aviation Corps), the predecessor of the Italian Royal Air Force founded in 1923.
Guidonia was erected as a comune in 1937 by Benito Mussolini, its name chosen to honour the Regia AeronauticageneralAlessandro Guidoni (1880–1928), who had died on 27 April 1928 while testing a new parachute at the air force facilities.
^"Demography in Figures". Istituto nazionale di statistica (ISTAT). Archived from the original on 2017-06-22. Retrieved 2010-02-12. for August 2009
^"Guidonia Climate Normals 1991–2020". World Meteorological Organization Climatological Standard Normals (1991–2020). National Oceanic and Atmospheric Administration. Archived from the original on 27 August 2023. Retrieved 27 August 2023.