The Latin word castra, with its singular castrum, was used by the ancient Romans to mean buildings or plots of land reserved to or constructed for use as a military defensive position. As the word appears in both Oscan and Umbrian (dialects of Italic) as well as in Latin, it probably descended from Indo-European to Italic. The terms Roman Camp and Roman Fort are commonly used for castra. Types of castra The best known type of castra's the camp, a military town designed to house and protect the… (More on Castrum)