Rochester Castle was built within the existing defences of a former Roman fortified town. The site was strategically important due to its bridge over the River Medway and accordingly the castle was raised in the immediate aftermath of the Norman invasion. Within a few decades it had been rebuilt into a substantial fortress dominated by a Great Keep.



The Romans


Rochester is situated within a loop in the River Medway and, until the modern era, was at the lowest bridgeable point. The site may have been the location where the Battle of Medway (AD 43) was fought in the earliest phase of the Roman invasion. In this action, mounted Batavian troops forded the river and defeated the British warlord Togodumnus. Shortly after, as the Romans consolidated their hold on southern England, a bridge was constructed at the site linking Canterbury (Durovernum) and Dover (Portus Dubris) with London (Londinium). A fort may have been established nearby at the same time although this has not been located and evidence may have been obliterated by the later medieval castle.


If a fort was established at Rochester, it probably had a relatively short lifespan and the site was soon adapted into a civilian settlement which served as the administrative centre (civitas) of the Cantiaci tribe. It was known as Durobrivae which means 'town or fort by the bridges'. A town wall, consisting of an earth rampart fronted by a ditch, was built during the late second century AD. This enclosed an irregular wedged shaped area of 23 acres which extended from the river. It was probably constructed for taxation and administrative purposes rather than defence but was rebuilt in stone circa-AD 225. The town remained occupied until the withdrawal of Roman forces in the fifth century AD but then went into decline.


After the Romans


Around AD 604, King Ethelbert of Kent founded a cathedral dedicated to St Andrew on the site and established the Bishopric of Rochester. Together with the crossing, Rochester once again developed into an important town. It was devastated in an attack by Aethelred of Mercia in AD 676 and by the Danes in AD 842 but on each occasion the town regenerated. The old Roman defences were also enhanced enabling the town to successfully resist another attack by the Danes in AD 884.


The First Castle


Rochester Castle was raised by William I in the immediate aftermath of the Norman invasion. The crossing point over the Medway was a key nodal point ensuring the Normans could advance on London but still have secure access back to the south coast and thus Normandy. The fortification was an earth and timber ringwork castle built in the south-western corner of the former Roman town defences. The new castle straddled these ancient walls, presumably to reduce construction time.


In 1067 William I granted the title of Earl of Kent to his half brother Odo, Bishop of Bayeux. This came with a large package of lands including Rochester which became one of his primary residences. Odo still held the fortification when William I died in 1087 and ownership of Normandy and England was divided between his two eldest sons, Robert Curthose and William Rufus. Like most magnates, Odo owned lands in both territories and wanted a single ruler. When Rufus was crowned as William II of England, Odo rebelled.  The new King mobilised his forces and successfully captured Odo at Pevensey Castle. He was taken to Rochester, where his men refused to surrender to the King, and an attempt was made to compel them to capitulate. Instead, the garrison sallied out and rescued Odo taking him back into the town. The infuriated William besieged both castle and town for several weeks before the garrison ultimately surrendered after which Odo went into exile.


Stone Castle


Following its capture by Royal forces, William II instructed the castle to be rebuilt in stone and entrusted the task to Gundulf, Bishop of Rochester. Despite his ecclesiastical calling, he was a proficient castle builder having previously constructed the White Tower in London. The timber walls of the first castle were demolished and replaced with a new stone built curtain wall. Concurrently he also started rebuilding the Cathedral.


In 1127 Henry I granted custody of Rochester Castle to William de Corbeil, Archbishop of Canterbury on the condition that he strengthen the defences. Accordingly work started on the Great Keep the same year and continued through to its completion in 1136. This vast tower was one of the largest of its type and still dominates the skyline of the modern town.

The stone curtain wall was built by the Bishop of Rochester in the late eleventh century. Thirty years later, the Archbishop of Canterbury added the Great Keep.

First Barons' War


In 1215 relations between King John and his barons were at the point of collapse. The sealing of Magna Carta was an attempt to secure a peace but, when John revoked it, the country descended into civil war. With London in the hands of the rebellious barons, the King started raising an army in Kent comprised largely of mercenaries imported from the continent. To protect London, the barons moved to secure Rochester with its strategically important crossing over the River Medway. At this time the castle still formed part of the estates of the Archbishop of Canterbury and the then incumbent, Stephen Langton, had a fractious relationship with the King. Accordingly Rochester Castle offered no resistance when a baronial force under William de Aubigny and Robert Fitzwalter occupied it.


As soon as he heard of the capture of Rochester Castle, King John moved his forces to recover it. On 12 October 1215, John's army defeated Robert Fitzwalter and seized Rochester bridge. However, the castle's garrison remained defiant forcing the King to besiege the fortification. Having tried and failed to storm the castle or to destroy its walls with siege machines, the Royal army concentrated on undermining the structure. The mine had been constructed by late November 1215 as John instructed his Justiciar to send him "40 pigs too fat for eating, to raise a fire under the tower". The fat from these animals was used to burn the timber props that had been placed under the castle's masonry. The resultant destruction included the collapse of the western corner of the Great Keep, one of the outer towers and a portion of the curtain wall.


Despite the catastrophic destruction of their castle, the rebels retreated into the undamaged portion of the Keep but their supplies were limited and they surrendered a few days later. The King was initially minded to execute every rebel within but was dissuaded from doing so on the basis it would set a precedent of brutality that would inevitably have been copied by the rebels. Instead, he executed just one person, a crossbowman, whom King John had known since childhood.


Henry III


The First Barons' War had left Rochester Castle in a sorry state and in 1217 Henry III commenced repairs to the curtain walls and later rebuilt the collapsed portion of the Great Keep. The repairs were timely for in 1264, during the Second Barons' War, the castle was besieged once again. This time a pro-Royalist garrison was in situ and rebel army under Simon de Montfort, Earl of Leicester attempted to capture it. In conjunction with his ally - Gilbert de Clare, Earl of Gloucester - he launched a two pronged attack that successfully seized the Bailey. The defenders retreated into the Keep and burnt the buildings in the bailey as they withdrew including the Great Hall. They successfully held out until Montfort's force had to withdraw but, later in 1264, Henry III was defeated at the Battle of Lewes and Rochester Castle was handed over to the rebels. It remained in their custody until the defeat of the rebellion the following year.




Repairs were made following the Second Barons' War but the Great Hall was not rebuilt and, unusually, the Great Keep became the main residential area in the castle. This made it a less attractive residence and in the subsequent century the Royal manor at Gravesend was often used instead of Rochester. Furthermore, Edward III commissioned Queensborough Castle as a new residence effectively eclipsing Rochester. However, in 1381 the collapse of Rochester bridge and the storming of the old castle by an angry mob, prompted Richard II to invest in the site. A new bridge was built and the castle received a new North-West bastion which was fitted with artillery to command the new crossing.




By the mid-sixteenth century the River Medway was becoming increasingly important as a port and anchorage for the Royal Navy. To protect the river, Upnor Castle was built downstream. Stone was robbed from Rochester Castle to support the construction effort. At some point thereafter Rochester Castle was gutted by fire and was never rebuilt. The structure drifted into ruin but it was purchased by Rochester Corporation in 1884 and opened to the public.





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What's There?

Rochester Castle is a hugely impressive early Norman Keep. Also visible are the remains of the bailey curtain wall and towers. Most of the town walls have gone but segments of the east wall survive.

Rochester Castle and Town Walls Layout. The original Roman town was a wedge shaped enclosure that extended from the river. The castle was built in the south-west corner of the Roman defences in the immediate aftermath of the Norman invasion. The town wall was extended to the south in the early fourteenth century and Priory Gate was built at this time. Within a few decades this was still deemed to be too restrictive and the town wall was extended further south.

Great Keep. The Keep was built by William de Corbeil, Archbishop of Canterbury in the late 1120s. It originally had square towers on each corner but, following the collapse of the western corner during the 1215 siege, this was rebuilt in a circular shape.

Keep Entrance. The Keep originally had a guardroom that controlled access into the Keep.

Keep Interior. The internal flooring of the keep has been removed but the lavish masonry can still be appreciated and the view from the parapet is superb.


Curtain Wall Tower.

Curtain Wall / Henry II Chambers.

North West Tower. The tower was added by Richard II and mounted artillery to cover new Rochester bridge. The gateway is a Victorian addition.

Rochester Bridge. Rochester is located at the lowest bridgeable point of the River Medway. The Romans constructed the first known bridge and, using their stone piers, this crossing was maintained through to the fourteenth century. A particularly harsh Winter caused irreparable damage prompting construction of a new bridge between 1381 and 1396. This medieval crossing, which was fitted with a drawbridge, was demolished in 1857 and replaced with the current crossing.

Rochester and River Medway. Rochester Castle as viewed from the Napoleonic era Fort Amherst. Beyond the castle the River Medway flows through the North Downs and then into the Thames Estuary. Rochester was the probable site of the Battle of Medway (AD 43) where Roman auxiliary forces, predominantly Batavian cavalry, crossed the river and routed the British tribes under Togodumnus.

Town Walls. Two bastions and one gate survive from the town walls. The surviving gate is Priory Gate which was an early fourteenth century addition when the town walls were extended to the south. Within fifty years the line of the wall was moved again and this is undoubtedly why Priory Gate survived.

Town Walls. Short segments of the town wall survive.

Cathedral. The Cathedral was initially founded by King Ethelbert of Kent in AD 604 but was rebuilt by the Normans.

Medway Defences. The first fortification was Rochester Castle, built at the crossing point over the river. In the mid-sixteenth century Chatham dockyard was established prompting construction of Upnor Castle. Later further defences were built ever further west and the eighteenth and nineteenth century saw landward defences constructed.

River Medway. After passing Rochester, the River Medway flows through the North Downs and out into the Thames estuary.

Getting There

Rochester Castle is located to the north of the town and well signed posted. There is pay and display parking on road by the waterfront or in small car park adjacent to castle. The surviving segments of the town walls are concentrated in the south off Blue Boar Lane and Crow Lane.

Car Park Option

Esplanade, ME1 1LF

51.390335N 0.500670E

Rochester Castle


51.389894N 0.501368E

East Bastion / Car Park

Blue Boar Lane, ME1 1PD

51.388557N 0.506084E

Priory Gate

No Postcode

51.388355N 0.502324E