When two wealthy medieval knights established a fund to ensure a river crossing in Rochester would remain in place forever, they might have hoped their desire would last but may not have expected their legacy to continue as long as it has.

But the Rochester Bridge Trust remains in existence to this day 621 years later and is as resolute as the foundations it was built on centuries ago with the latest accounts showing the Trust is worth £114 million.

Having seen dozens of incarnations, the crossings over (and later under) the River Medway in the town centre are used by thousands every day without any cost to the taxpayer or tolls according to the founding ancient motto "publicas privatis", meaning "from the private for the public".

The colourful past of the trust has seen it embroiled with royalty, civil war, Charles Dickens and Dick Whittington.

A crossing in Rochester was first established by the Romans soon after the invasion under the emperor Cladius in 43AD to link the fort at Richborough and Dover to London along Watling Street.

Archaeological discoveries in the mid-19th century found nine stone pillar foundations constructed below the river bed.

On top a timber roadway was constructed of three broad oak beams across each pier and planks laid across.

For centuries after the Romans were defeated, noblemen, the King's estates, archbishops and bishops of Rochester were responsible for making sure their dedicated section of the bridge was kept in good repair.

A Royal Commission would decide who was responsible when repairs were identified.

It remained in place for hundreds of years until a bitterly cold winter in 1381 which even saw the River Medway frozen over completely.

According to medieval chronicles, when the ice melted in February the pressure caused by flood water and ice collapsed part of the original Roman bridge.

Step in Sir John de Cobham – a powerful landowner in Kent at the time – who was appointed under a Royal Commission in 1382. He enlisted the help of Sir Robert Knolles to pay for a new bridge 100 yards upstream from the remains of the Roman bridge.

Construction began in 1387 and was completed four years later. It remained the only river crossing for almost 500 years.

It was 560ft long and 14ft wide made up of 12 pillars with a wooden drawbridge five arches in from the Strood side.

Sir John and Sir Robert petitioned the king, Richard II, receiving a royal patent in 1399 to establish the Wardens and Commonality of Rochester Bridge – wardens are still appointed today.

The patent meant the two knights could own property and use the income to maintain the bridge and Sir John – along with further royal grants from Henry IV and Henry V during the 15th century – accumulated land in Kent, Essex and London.

They bought up swathes of land in London – Leadenhall Street and Shaft Alley close to Leadenhall Market – and various plots including manors such as South Hall in East Tilbury, Rose Court on the Isle of Grain, Langdon, Nashenden and Little Delce in Rochester and farms in Dartford and Frindsbury along with many wharves, inns and plots in Rochester and Strood.

The portfolio was virtually unchanged until the 19th century and many of the properties are still under the Rochester Bridge Trust's ownership today with the rent and income used to fund works on the bridges which straddle the Medway between Rochester and Strood.

As a result, no public funding is used to maintain the bridges.

The trust holds thousands of archive documents dating back right to the very start of the first royal assent granted to Sir John and Sir Richard.

The earliest documents are written in Latin with many in French as well. It wasn't until Henry VIII ascended the throne more documents were written in English but Latin was still prevalent in legal documents right up to the mid 1700s.

The archives are stored and managed by the trust and feature scores of episodes of the bridges' uses and incidents, disasters and everything ever associated with maintaining the vital river crossing.

Alison Cable, the trust's current archives and records manager, notes how the Medieval Bridge was host to one of England's bloodiest chapters in history.

"The medieval bridge was made of stone arches, with one span a wooden drawbridge.

"This isn’t a drawbridge as we imagine them (there was no mechanism for lifting and lowering at will – but it could be removed as it was in June 1648, when the bridge played host to a bloody Civil War battle.

"In preparation for the Parliamentarian attack, the royalists removed the drawbridge and mounted more than 40 cannons on fortifications erected on the riverbank and on the bridge.

"The royalist troops held Rochester for the king, but when General Fairfax marched up the east side of the Medway, having defeated the royalists the previous night at the Battle of Maidstone, the royalists retreated across Rochester Bridge to Gravesend, where they escaped over the Thames into Essex, having first destroyed the drawbridge at Rochester so that Fairfax could not follow them.

"The accounts for 1648-1649 include a payment of 1s. 6d. to 'two men for saving the planckes of the draw bridge which was throwne into the River by soldiers'.”

In the late 1850s, the Royal Engineers based at Brompton barracks volunteered to demolish the medieval bridge to make way for a replacement.

They used 2,459 pounds of gunpowder at a total cost of £64 11s – approximately £5,000 in today's money.

Much of the rubble was used to create Rochester Esplanade and some was recycled to build parts of Chatham Dockyard.

Stories of rockeries, walls or other structures across Rochester and Strood have never been proved or disproved.

One of the balustrades added during the Georgian period was given to Charles Dickens which he used as a sundial at his home, Gads Hill Place in Higham.

In 1846, the government passed the Rochester Bridge Act granting the Wardens and Assistants of Rochester Bridge permission to replace the old medieval bridge.

Following the line of Watling Street where the original Roman bridge once stood, it was officially opened on August 13, 1856 in a ceremony attended by mayors and aldermen of Rochester and Maidstone and joined by a Royal Marine band.

Fireworks and a public dinner rounded off the celebrations.

But some 50 years later, despite the pomp and ceremony to the grand opening, the Victorian bridge had been consigned to the scrapheap in desperate need of refurbishment.

Further bridges adjoining the road bridge had been constructed to carry the railways which boomed during the second half of the 19th century.

Both the East Kent Railway in the 1850s and the South Eastern Railway Company in the 1880s added railway crossings over the Medway and the swing bridge – which was never even opened – was redundant.

Utility companies applied to carry pipes across the Victorian swing bridge in the 1890s and it was permanently closed.

But by 1909 a new bridge was once again needed due to severe damage, fractures and missing or defective bolts across the structure.

The following year, after considering several designs from engineer John Robson, plans were approved for it to be reconstructed. Now known as The Old Bridge – which carries traffic along the A2 from Rochester to Strood – it opened on May 14, 1914 at a cost of £95,887 (£7.5 million).

Following the Second World War, with more than 32,000 vehicles crossing the Old Bridge every day, it was decided to renovate the 1850s railway bridge to create two lanes of traffic in each direction.

An act was passed in 1965 and land was acquired by the wardens and assistants with construction starting in July 1967 and opened by Princess Margaret three years later.

All three of the bridges constructed since 1910 are still in use today for road traffic and the third carries utilities from one side of the Medway to the other. The other bridge carrying trains over the river is owned by Network Rail.

The trust was also influential in the construction of the Medway Tunnel in the late 1980s when new transport infrastructure was required.

It no longer owns the tunnel, which was opened by Princess Anne – once again demonstrating the unity with the Royal Family – in August 1996.

Medway Council took over the ownership in 2008 for £1 as it became the first river crossing in Medway to come under public ownership, although that has not come without its controversy due to the high costs of maintaining it for taxpayers.

The government awarded the council £5m to carry out repairs following fears there was not enough funding in the authority's budget to carry out the work.

So, what does the future hold for this historical and somewhat unique and fascinating chapter of Kent's history?

The trust is embarking on the biggest refurbishment project since the New Bridge was built in the 1960s and with a reliance on a property portfolio for its income and stock market investments, has taken a hit during the recent Covid-19 crisis, says bridge clerk and chief executive of the trust Sue Threader.

"Nonetheless, we are in a sound position to meet our current liabilities. The whole point of our very long-term financial planning is to make sure we have the resources to do work when it is needed.

"We’ve learned a lot about the bridges as a result of the works. On the whole they are in excellent condition, which is testament to our programme of ongoing maintenance.

"That said, every large engineering project encounters unexpected issues, and the same can be said in Rochester, where we’ve occasionally opened an area of the structure up and realised we might have to do a little more work to for example, an area of concrete or steel.

"Not forgetting the incidence of a pandemic to add to the challenge.

"Much of the work that has been completed is behind the scenes – underneath the bridges.

"This will ensure the bridges continue to serve the travelling public and communities of Rochester and Strood for decades to come.

"Work on the New Bridge is almost complete.

"The work currently being carried out includes repairs to the swing bridge section of the Old Bridge, a culvert will be soon built under Rochester Esplanade, and then we’ll be upgrading the ornate lighting.

"We have plans to move on to the refurbishment of the Bridge Chapel and Bridge Chamber and the long-term development of the Bridge Heritage Quarter, however we will be cautious about progressing these too soon because of the financial impacts of Covid-19.

"We may have to take things a bit slower than we had originally planned, but we still intend to complete this project within the next couple of years.

"We also have wider plans for the development of more education projects and exhibitions, the timing and format of these will depend on the Covid-19 recovery."

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