41°38′25″N 13°30′49″E / 41.640415°N 13.513699°E
 | This article relies largely or entirely on a single source. (October 2022) |
The Castle of Monte San Giovanni is a medieval fortress in Monte San Giovanni Campano, Lazio, central Italy, built in the 11th century. The castle is known as the place where Thomas Aquinas was imprisoned by his family ca. 1240 to 1242 in an attempt to dissuade him from joining the Dominican Order. It is also the first fortification ever to be breached because of shelling from portable artillery, in 1495.