Portsmouth’s historic role as a naval base derives from its position guarding the narrow entrance to Portsmouth Harbor. Richard I built the first dockyard here. Its importance increased with the Hundred Years War and the town that developed around it inevitably became a target for French attacks. Following a royal survey in 1386, an earth rampart was raised around the landward sides of the town. From 1560, the rampart continued along the sea front and strengthened elsewhere by a series of arrowhead bastions.
Charles II’s engineer, Bernard de Gomme, undertook more works. The defenses were further elaborated over the next two centuries but Lord Palmerston’s astonishing ring of fortifications, built in the 1860’s, rendered them obsolete. The complex of ramparts, bastions and outworks facing inland was demolished and only the seaward defenses remain.
The oldest of the visible defenses of Portsmouth is the Round Tower, on the promontory known as The Point. Here the entrance to Portsmouth Harbor is just a few hundred yards wide and a boom chain ran across from this tower to another on the Gosport side. One of the earliest buildings devised for defense by artillery, the Round Tower was built in 1415 – a year which brought victory for England but alarm in Portsmouth.
The present gun embrasures, widely splayed for greater range, were inserted in Henry VIII’s reign and the upper part of the tower was rebuilt during the Napoleonic Wars. From the Round Tower a Victorian gun battery leads towards the Square Tower, built in 1494, but refaced in 1827. It is here that the town’s perimeter defenses bagan.
Beyond another gun battery is the Saluting Battery, a stone platform for cannon which projects out a little from the rest of the defense line. It is he only unspoiled bit of Elizabethan work remaining.