Portus Adurni

Part of a series on the
Military of ancient Rome 753 BC – AD 476
Structural history Army Unit types and ranks Decorations and punishments Legions Auxilia Generals Navy Fleets Admirals
Campaign history Wars and battles
Technological history Military engineering Castra Siege engines Triumphal arches Roads
Political history
Strategy and tactics Infantry tactics
Frontiers and fortifications Limes Walls Limes Britannicus Antonine Wall Hadrian's Wall Saxon Shore Limes Germanicus Alb Limes Lauter Valley Limes Lower Germanic Limes Main Limes Neckar-Odenwald Limes Upper Germanic-Rhaetian Limes Wetterau Limes Danube–Iller–Rhine Limes Norican Limes Claustra Alpium Iuliarum Pannonian Limes Limes Alutanus Limes Moesiae Trajan's Wall Anastasian Wall Limes Sarmatiae Limes Arabicus Limes Tripolitanus Limes Mauretaniae
Ancient Rome portal
v t e

Portus Adurni was a Roman fort in the Roman province of Britannia situated at the north end of Portsmouth Harbour. It was part of the Saxon Shore, and is the best-preserved Roman fort north of the Alps.^[1] Around an eighth of the fort has been excavated.^[2]

It was later converted into a medieval castle known as Portchester Castle.