Upper German-Raetian Limes
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About
The Upper Germanic-Rhaetian Limes (German: Obergermanisch-Raetischer Limes), or ORL, is a 550-kilometre-long section of the former external frontier of the Roman Empire between the rivers Rhine and Danube. It runs from Rheinbrohl to Eining on the Danube. The Upper Germanic-Rhaetian Limes is an archaeological site and, since 2005, a UNESCO World Heritage Site. Together with the Lower Germanic Limes it forms part of the Limes Germanicus.
The Limes used either a natural boundary such as a river or typically an earth bank and ditch with a wooden palisade and watchtowers at intervals. A system of linked forts was built behind the Limes.
Adapted from Wikipedia (CC BY-SA)。Photography via Wikimedia Commons.