Cow Tower, Medieval City Walls Norwich

Cow Tower is arguably the first artillery tower built in England, between 1398 and 1399.

Cow Tower was intended to defend the north-eastern approach to Norwich with hand cannons and bombards. It stood apart from the main city walls, close to the river where its height would have allowed it to fire along the river Wensum to the south and to the west, and onto the higher ground opposite the city. The Tower was designed to hold a garrison when required and was well furnished, probably using different floors for dining and sleeping.

Norwich was a prosperous city in the late 14th century, with a population of around 5,000 and a centre of the international cloth trade. Between 1297 and 1350 the city had erected a circuit of defensive stone walls and ditches, both to impress upon outsiders the status of Norwich as a great city, but also to defend against invasion or civil disorder.

Fears grew about the threat of French raids across England from the 1380s onward. The citizens of Norwich were particularly concerned about the potential of a French raid on the city, drawing parallels between the position of Norwich and the experience of Southampton, another trading city that had been devastated by a French attack in 1338. This threat, combined with the recent Peasants Revolt of 1381 when the rebels had looted the city, encouraged the local government to improve further the city's defences.

Gunpowder weapons had begun to be introduced into England in the early 14th century, initially being used as offensive siege weapons but rapidly being adapted for defensive purposes during the 1360s. Although they were expensive, by the 1380s their potential value in defending castles and city walls was well understood.

Norwich had acquired gunpowder weapons and a team of gunners by 1355, and by 1385 had fifty gunpowder pieces for use along its city walls.

The Cow Tower was built on a strategic and hard to defend approach to Norwich on a bend in the River Wensum, in a meadow called Cowholme. It was intended to function as a specialised artillery tower, housing gunpowder weaponry capable of suppressing attackers on the far side of the river.

The Cow Tower was one of several fortifications along this stretch of the river, with the gatehouse of Bishop Bridge lying just to the south, followed by two boom towers that controlled access to the waterway a further 1 kilometre down-river. Although the Cow Tower was not directly part of the city walls, a protective timber palisade linked the tower with the line of the city wall to the north-west, and ran south to meet Bishop Bridge.

The city's accounts show the details of the payments for the construction of the tower between 1398 and 1399, including charges for 36,850 bricks, stone, sand, lime, a hoist and various equipment.

During Kett's Rebellion in 1549 the rebels fired on the Tower from the heights of Mousehold opposite, although the Tower does not seem to have been unduly damaged.