Societa Sportiva Dilettantistica a r.l. Eretum Monterotondo Calcio , known as just Eretum Monterotondo is an Italian football club based in Monterotondo, in the Metropolitan City of Rome Capital (former Province of Rome). Eretum Monterotondo was found in 2016 by the merger of A.S.D. Monterotondo Calcio and A.S.D. Eretum. A.S.D. Monterotondo Calcio itself, was founded in 2013 by the merger of A.S.D. Citta di Marino Calcio and A.S.D. Atletico Monterotondo. However, the team considered itself as the successor of Polisportiva Monterotondo Calcio, that originally founded in 1935. That team, known as Polisportiva Monterotondo Lupa in 2013, was relocated to Maccarese to claim as the successor of another team, A.S. Giada Maccarese.
A.S.D. Atletico Monterotondo was a team from Monterotondo.
In 2012–13 season, the club finished as the 10th in the group B of 2012–13 Prima Categoria Lazio, one position higher than A.S. Eretum. The division was the 8th highest level in the Italian football league pyramid and the 3rd level from the bottom at that time.
At the end of 2012–13 season, the major team of the city, Polisportiva Monterotondo Lupa, sold its position in Serie D, by relocated and renamed to Maccarese, as a replacement of A.S.D. Maccarese Calcio. Serie D, or the 5th highest division at that time, was one level below the lowest professional division, Lega Pro Seconda Divisione. However, at the same time, Atletico Monterotondo was merged with another team also from the Province of Rome, A.S.D. Citta di Marino Calcio. Citta di Marino participated in 2012–13 Serie D and relegated to 2013–14 Eccellenza Lazio. The new major team of the city was denominated as A.S.D. Monterotondo Calcio. The new registration number of the club was 937,688.
In terms of city, only the team from Marino disappeared in the shuffles. The two relocations effectively made Maccarese "promoted" to Serie D by using the spot of Monterotondo Lupa; Monterotondo retained in Eccellenza Lazio by using the spot of Mari