Square Tower Portsmouth: History and Uses

What is Square Tower in Portsmouth?

Square Tower is one of the oldest parts of the fortifications of Portsmouth, England. It is a Grade I listed building, built in 1494 during the reign of Henry VII, and forms part of Portsmouth's sea walls.

Its history is closely tied to the defence and administration of the naval port. The RULE PORTSMOUTH! route visits Square Tower at stop 11 of 13, placing the building within a wider exploration of Portsmouth's historic landmarks.

The tower's importance comes from this combination of age, position and changing purpose. It was not simply part of the city's defensive walls: over the centuries, it also housed the Governor of Portsmouth and stored supplies for the Royal Navy.

What was Square Tower used for?

Square Tower was the home of the Governor of Portsmouth until 1584, when the position moved to Domus Dei. The Governor of Portsmouth remained the honorific head of the Naval Port until 1834, so the office continued to hold significance after the governor's residence had moved elsewhere.

During the Siege of Portsmouth in 1642, part of the Cromwellian Civil War, Square Tower held about 1,200 barrels of gunpowder. The Royalist side used the gunpowder stored in the tower as a negotiating tactic during the siege.

In 1779, safety concerns led to the gunpowder being replaced with Royal Navy meat storage. Square Tower continued in that role until 1850, giving the building another practical use within Portsmouth's naval history.

These changes mark a clear shift in the tower's documented role: from the residence of Portsmouth's governor, to a strategically important store during conflict, and then to a storage place for Royal Navy provisions.

What is Square Tower used for now?

Square Tower is now used for weddings. Its present use contrasts sharply with its earlier roles in Portsmouth's defences and naval supply: the same building that held gunpowder during the 1642 siege and meat storage until 1850 now hosts weddings.

To place that change in the building's longer history, follow the RULE PORTSMOUTH! route when you reach Square Tower. The stop connects the Grade I listed building beside Portsmouth's sea walls with the changing purposes recorded across its history.