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Here is an article discussing a series of books documenting the ancient Roman frontier network. The project began with efforts to have the limes in Upper Germany recognized as a World Heritage Site. This required more thorough documentation of the 550 km-long Roman frontier. This initial effort was the first of twenty books written over a span of twenty years to comprehensively document the entire Roman frontier.
https://the-past.com/feature/encircling-the-empire-how-romes-frontier-network-was-chronicled/