Passau-Innstadt Roman Fort
About
Emperor Domitian's engineers raised this small castellum on the Noric bank of the Inn river, right where Noricum met Raetia at the westernmost edge of the Danube frontier. The fort sat directly across the water from where a much larger Batavian cohort base would rise decades later, splitting the border town of Passau between two provinces long before it became one city. Its garrison watched over a critical river junction where the Inn, Ilz, and Danube all meet. Modern Passau's Roman museum, built over the old fort site, now walks visitors through a reconstructed timeline of the frontier post.
What happened here
Five hundred men, sometimes a thousand, recruited from a province rather than from citizens, and often stationed a long way from where they were raised. Cavalry units get a bigger fort and far more stabling; the smell tells you which kind you are in before the plan does. The layout copies a legionary fortress at a quarter of the size — headquarters, commander's house, granaries, barracks, a bath house usually built outside the walls because of the fire risk. Duties are patrolling, escorting, customs, and policing rather than pitched battle. After twenty-five years a man is discharged with citizenship for himself and his children, recorded on a bronze diploma he keeps for life. A village grows outside the gate within a decade.
Sources
Nearby
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