WHEN one thinks of the history of Bury images of towering mills and a proud industrial heritage immediately spring to mind ­— an era when the town rose to become the progenitor of ideas, technology and manufacturing which revolutionised the world.

But few may conceive just how deep the town's roots go.

In the early 1970s an extraordinary archaeological dig uncovered evidence that redefined people's understanding of the town.

Organised by Norman Tyson and Bury Archaeological Group, the dig opened a window on Bury's medieval past, and revealed that it was home to that most iconic edifice of the Middle Ages ­— a castle.

The principal aim of the dig, which took place almost 50 years ago this week, was to locate the castle’s wall and pinpoint them on the street plan of the area.

In July 1973, with the help of a JCB digger, the group's members and volunteers sunk their trowels and muddied their boots in a trench dug in a carpark opposite the Bury Drill Hall ­— to immediate success.

It was initially thought that they had struck the 14th century inner wall, but was later discovered to be the thinner, but still very substantial outer wall.

Remains of Bury Castle had accidentally been found once before, in 1865, when workmen carrying out sewerage work unwittingly excavated the walls of a keep or tower.

Another portion was stumbled upon almost 200 years ago when workmen were sinking a small gasometer in the yard of the nearby Two Tubs pub.

It was feared that the Victorian workers may have stripped the site of any finds. But happily this was soon proven wrong and the dig exceeded all expectations.

Bury Times: Bury Castle excavations near Bury Drill Hall. Photo: David Dixon reused under Creative Commons Liscence https://creativecommons.org/licenses/by-sa/2.0/Bury Castle excavations near Bury Drill Hall. Photo: David Dixon reused under Creative Commons Liscence https://creativecommons.org/licenses/by-sa/2.0/

Through their excavations the archaeological group were able to map the castle's walls and moat.

Alongside the incredible architectural discoveries, a profusion of artifacts from the medieval and Tudor periods were unearthed, including stained glass, drinkware, pottery, tracery from a trefoil window, the base of a wooden bowl and other wooden items, and leather shoes miraculously preserved by the clay of the former castle moat.

There were also a plethora of 19th century finds including glass beer and mineral water bottles ­— some from makers previously unheard of to the archaeologists ­— and brown glazed pie dishes.

Among the final objects freed from the earth were traces of a turf wall and a half-pound stone Petard cannon ball ­— said to evidence that the castle was a fortress rather than a showpiece, according to Dr Derek Janes, then assistant curator at Bury Museum, commenting at the time.

Bury Times: Members of Bury Archaeological Group during the dig at Bury Castle, opposite Bury Drill Hall, in 1973Members of Bury Archaeological Group during the dig at Bury Castle, opposite Bury Drill Hall, in 1973

After the week was up the dig site was filled in, the secrets once again hidden, and the land returned to carpark status.

Moves were quickly made to have the ancient monument scheduled, even though it remained underground, and many called for the area to be permanently uncovered to show the remains of the castle wall.

It was recognised that before it could be opened to the public the site would require extensive engineering, drainage and other works to make safe the area ­— at least nine feet below street level.

Looking back on the dig, Norman Tyson spoke to the Bury Times about the archaeological group's groundbreaking discoveries.

While local historians had previously reinterpreted pre-existing information about the castle, “what we did was really entirely new”, he said.

The group's excavations shook off assumptions that Bury’s past was limited to mills, factories and industry, and highlighted that the town had 'such an ancient past'.

“It brought to life the history and helped people to properly realise the antiquity of their own environment," Mr Tyson said.

“I think the general public were a little bit surprised to see something so ancient appearing like that.

"That was some consolation. As was being able to fit the town's history together."

Bury Times: Norman Tyson, group secretary of Bury Archaeological Group, surveying stonework which marks the line of Bury Castle's wall, in 1973Norman Tyson, group secretary of Bury Archaeological Group, surveying stonework which marks the line of Bury Castle's wall, in 1973

Further digs in the 1970s revealed six distinct phases of development and eventual decline at Bury Castle.

The castle dates to at least 1315 and was developed and aggrandised on the site which had been occupied by earlier, more modest manor houses belonging to the de Bury family.

The manor was well situated, occupying a high vantage point beside the River Irwell, and close to the parish church and market place.

In the early 14th century the manors of Bury and Pilkington were merged through marriage of Alice de Bury and Roger de Pilkington.

Their descendant, Thomas de Pilkington, was granted permission in 1469 to fortify his manor house, by 'license to crenellate', into what would become Bury Castle.

The fortifications saw the addition of buttressed curtain wall, a newly constructed tower house, a bridge, and the castle's the moat was remodelled and widened.

However, the Pilkington's were Yorkists, and during The Wars of the Roses sided with King Richard III.

Thomas de Pilkington even fought in the final battle of the wars, at Bosworth Field, in which Richard was killed.

Meanwhile, biding his time on the sidelines of the battlefield was the ambitious Thomas Stanley, who held back his troops to commit to which ever army looked likely to take the day and the spoils of victory.

After the battle Pilkington's lands were confiscated, and Bury Castle passed to Stanley, the newly made Earl of Derby, by Henry Tudor who ordered the castle be razed to the ground.

Whether the King's commands were followed to the letter, or the fortress was idly permitted to fall into decrepitude by the absent Earl, has been widely debated.

But by the following century Bury Castle was no more than a ruin.

Bury Times: Derek Janes, assistant curator of Bury Museum, and Betty Popham of Bury Archaeological Group, with a piece of widow tracery found during a dig at Bury Castle in 1973Derek Janes, assistant curator of Bury Museum, and Betty Popham of Bury Archaeological Group, with a piece of widow tracery found during a dig at Bury Castle in 1973

However, Mr Tyson believes the castle suffered no sudden and vengeful destruction, and was instead allowed to decay before being progressively dismantled during the early modern period, as people scavenged valuable materials, such as timbers and sandstone from the crumbling edifice.

Over time its moat became choked with rubbish, and Mr Tyson theorised that it may have come to serve as a midden and public dump for the nearby market place.

Some 20 years on from Mr Tyson's dig, in 1999, the surviving, visible castle remains were restored for public viewing.

Finds from the digs can also be seen on display at Bury Museum.

Anyone interested in joining Bury Archaeological Group should visit facebook.com/buryarchaeology.