The terrain of Guidonia Montecelio is mainly flat, and the community lies in between the Via Nomentana and the Via Tiburtina.

It borders with Fonte Nuova, Marcellina, Palombara Sabina, Rome, San Polo dei Cavalieri, Sant'Angelo Romano and Tivoli.

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 Aeronautica general Alessandro Guidoni (1880–1928), who had died on 27 April 1928 while testing a new parachute at the air force facilities.

Guidonia is also home to Marco Simone Golf and Country Club, which was announced as the host of the 2022 Ryder Cup in June 2015, but with the COVID-19 pandemic postponing the 2020 Ryder Cup to 2021, subsequent matches were pushed back a year with Marco Simone then hosted the event in 2023.