The Navalia was a military port of Ancient Rome which may also have included a naval dockyard. It is thought to have been sited on the left bank of the river Tiber to the south of the Campus Martius and is sometimes called the 'Navalia superiora' to distinguish it from another military port further down the Tiber near the Forum Boarium (the 'Navalia inferiora'). The structures, probably gable roofed shipsheds of the period, were also mentioned as being used to hold hostages and circus animals, perhaps during the later period where silting meant navigation on the upper Tiber had become difficult.[1][2][3]