Portus Forum Iulii
About
Forum Iulii's stone harbor, nicknamed Claustra Maris or Sea Bolt, was built by Octavian after Actium as a third great naval base alongside Misenum and Ravenna, guarding the northwest Mediterranean. Its fleet, the classis Gallica, stayed active through the Julio-Claudian era but lost its standing amid the civil wars of 69 CE, after which its ships were reassigned toward Misenum and the Adriatic. The hexagonal harbor basin, once ringed by warehouses and now landlocked more than a kilometer from the sea, still survives as the Lanterne d'Auguste monument marking its ancient entrance.
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
Roman Maps shows the empire frozen at 11 August 117 CE, the day Trajan died — its moment of greatest territorial extent. Explore the full map →