From 1925 till 1991, with interruption, for obvious reasons, from 1933-1946 and then also a few years missing in the 1950s and 1960s, there was an event called "Gran Premio di Roma" for single seater cars. It started as Formula Libre (1925-1927), then had GP-status (1928-1932) and was then mainly a Formula 2 race, counting towards the European Championship from 1967 till 1984. From 1985 till 1991, the Grand Prix of Rome was a Formula 3000-round.
Most of the races took place at Vallelunga, 20 km north of Rome, but a few were held on other circuits:
1925 Monte Mario (winner Carlo Masetti, Bugatti T35)
1926 Valle Giulia, Parioli (winner Aymo Maggi, Bugatti T35)
1928 Tre Fontana (winner Louis Chiron, Bugatti T35C)
1929 Tre Fontana (winner Achille Varzi, Alfa Romeo P2)
1930 Tre Fontana (winner Luigi Arcangeli, Maserati 26M)
1931 Littorio (winner Ernesto Maserati, Maserati V4)
1932 Littorio (winner Luigi Fagioli, Maserati V5)
1947 Terme di Caracalla (winner Franco Cortese, Ferrari 125)
1949 Terme di Caracalla (winner Luigi Villoresi, Ferrari 166/F2)
1950 Terme di Caracalla (winner Alberto Ascari, Ferrari 166/F2)
1951 Terme di Caracalla (winner Mario Rafaeli, Ferrari 166/F2)
1954 Castel Fusano (winner Onofre Marimón, Maserati 250F)
1955 Castel Fusano (winner Jean Behra, Maserati 300s) (this was the only time the Grand Prix of Rome was a sportscar race)
From a (very) old thread.
The Tre Fontane circuit was created in 1928, a 13-kilometer road course between the Via Laurentina and Via Ostiense (at the time the place was pretty far from Rome, now... it is "center of Rome")
http://forums.autosp...w...t&p=1521061Another obscure Roman track was the "Circuito Ostiense". It was a motorcycle race which was held on 07 March 1926, a round of the Italian Championship, the winner was Tazio Nuvolari on a Bianchi "Freccia Celeste".
Nothing is known about this course. According to Italian contemporary press, the track was almost 13-kilometer long, "on the route of Via Ostiense".
The Via Ostiense is a 25-kilometer road from the Piramide Cestia in Rome, to Ostia, on the Tirrenian sea. It is not known wheter the circuit was at Ostia or at Rome.
Another street track was created at Ostia in 1939, the "Circuito dell'Impero" held on the promenade by the sea.
Possibly the stretch of the Via Ostiense which was used from 1928/30 in the Tre Fontane circuit, was the same of the "Circuito Ostiense" of 1926.
Who knows?