Castra Alteburg
About
The Alteburg fort on a low bluff south of Cologne was the headquarters of the classis Germanica, the Rhine fleet and the largest of Rome's provincial navies. More than a thousand marines were garrisoned here to patrol the river from the Rhine-Meuse delta up past the legionary fortresses, keeping the frontier's supply lines and communications running.
What happened here
The fleet is quartered here and the base is built around getting ships out of the water. Slipways and covered sheds keep hulls dry through the winter, because a warship left afloat waterlogs and slows. Crews are provincials serving long terms, not citizens, and they train at the oar constantly in the harbour. Workshops turn out rope, pitch, sailcloth and oars in quantity; timber is stockpiled seasoned. The main fleets patrol against piracy, carry dispatches and move troops, and in practice they spend far more time on transport than on battle. Detachments are posted away for years at a stretch. A large base needs a lighthouse, a mole and a town, and it gets all three.
Sources
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