page_title: Roman military engineering
section_title: Bridge building
hierarchical_section_title: Roman military engineering / Proactive and routine military engineering / Bridge building
caption_attribution_description: Deutsch: Trajansbrücke English: Trajan's Bridge
context_page_description: The military engineering of Ancient Rome's armed forces was of a scale and frequency far beyond that of any of its contemporaries'. Indeed, military engineering was in many ways institutionally endemic in Roman military culture, as demonstrated by the fact that each Roman legionary had as part of his equipment a shovel, alongside his gladius and pila.
  Fabri were workers, craftsmen or artisans in Roman society and descriptions of early Roman army structure attributed to king Servius Tullius describe there being two centuriae of fabri under an officer, the praefectus fabrum.
  Roman military engineering took both routine and extraordinary forms, the former a proactive part of standard military procedure, and the latter of an extraordinary or reactionary nature.
context_section_description: The engineers also built bridges from both timber and stone depending on required permanence, time available etc. Some Roman stone bridges survive to this day. Stone bridges were made possible by the innovative use of the keystone to allow an arch construction.  One of the most notable examples of military bridge-building in the Roman Empire was Julius Caesar's Bridge over the Rhine River.  This bridge was completed in only ten days and is conservatively estimated to have been more than 100 m (300 feet) long. The construction was deliberately over-engineered for Caesar's stated purpose of impressing the Germanic tribes, who had little experience of engineering, and to emphasise that Rome could travel wherever she wished. Caesar was able to cross over the completed bridge and explore the area uncontested, before crossing back over and dismantling the bridge. Caesar relates in his War in Gaul that he "sent messengers to the Sugambri to demand the surrender of those who had made war on me and on Gaul, they replied that the Rhine was the limit of Roman power". The bridge was intended to show otherwise.
caption: Trajan's Bridge across the Danube, the longest bridge for over a millennium
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