The hotly-debated identity of the Leaning Tower of Pisa’s creator has finally been confirmed as the 12th century sculptor-turned-architect, Bonanno Pisano.
He was long-believed to have masterminded the project, which is now a UNESCO World Heritage Site, but several other claimants have been considered over the centuries.
Italian scholars analysed a stone inscription first unearthed in 1838 from the base of the tower and claim it proves, beyond doubt, that Bonanno was the architect.
It also reveals that Bonanno was initially proud of his ‘marvellous work’ but was mortified when it started slumping, and had his connection to the project buried – literally.
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Italian scholars analysed a stone inscription first unearthed in 1838 from the base of the tower and claim it proves, beyond doubt, that Bonanno was the architect
WHO WAS BONANNO PISANO?
Little is known about the man who is thought to be the architect of the Leaning Tower of Pisa.
He was by trade a sculptor, crafting the bronze doors of Pisa cathedral.
But it is thought that in 1173 he began building the tower of Pisa, a 187ft tall bell tower.
Five years after construction began, the project was abandoned after one side sunk in the ground, causing a 5.5° slope.
Bonanno, who was initially immensely proud of his ‘marvellous work’ disappeared into obscurity.
It is thought that he died in 1200, never seeing his work become the beloved architectural gem known globally.
He was first speculated to be the architect by Giorgio Vasari, the 16th century biographer for Renaissance artists who was a painter, architect and writer himself.
But his mysterious and relatively undocumented life gave birth to theories that others, including architects Gherardo di Gherardo and Giovani di Simone, were behind the project.
Giulia Ammannati, a Latin expert from the Scuola Normale Superiore, a prestigious university in Pisa, examined the stone inscription.
When it was first discovered almost 200 years ago it was believed to come from Bonanno’s sarcophagus.
But Ammannati’s analysis discounted this possibility as the carved lettering was too long, with a further two lines of prose indicating there was more to the story.
Obscured over the 800 years since the tower’s construction by erosion, the Latin inscription was incredibly faint – but not illegible.
As well as his full name on the stone slab was the full inscription ‘Mìrificùm qui cèrtus opùs condéns statui ùnum, Pìsanùs civìs Bonànnus nòmine dìcor’.
Translated, this reads as: ‘I, who without doubt have erected this marvellous work that is above all others, am the citizen of Pisa by the name of Bonanno.’
Ms Ammannati, an expert in paleography, the study of ancient writing, tells The Telegraph that one word in particular exposes just how immensely proud the the ambitious architect was of his work – the adjective ‘cèrtus’.
”[It] expresses all his pride at being the architect. Bonanno erected the tower certain of its great beauty and confident that it would be an incredible monument,’ she said.
Before getting the commission to design the bell tower, he was best known for his work sculpting the bronze doors of Pisa cathedral.
His burgeoning emotions of pride and joy at his marvellous creation soon turned to despair and anguish as his beloved tower slumped to a precarious angle just five years after work began.
Leaning at up to 5.5° at its most wonky, the tower has since undergone immense restoration work to strengthen its foundations and secure it in place.
The issue was never with the tower itself, but with the land it was built on and its foundations.
The flawed design meant it had a foundation that was only three-metres deep and was set in weak, unstable subsoil.
As a result, the project was abandoned and following Bonanno death in the year 1200, he never saw his project turn into the national treasure and international icon it is today.
Before getting the commission to design the bell tower, Bonanno was best known for his work sculpting the bronze doors of Pisa cathedral (pictured)
But the weak ground continued to cause problems for the tower and its lean reached 5.5° by 1990. Since then, work has succeeded in rectifying some of the tilt. Left, at the most severe tilt in 1992 and right, after work corrected some of the lean
The tower as it was left half-built for more than 100 years following the discovery of its alarming tilt.
His shame at the failure of the construction is why the stone inscription was buried instead of taking pride of place, Bonannowanted his role in the erection of this architectural abomination to be lost over time.
Ms Ammannati said: ‘When the tower was half built it was already leaning due to the wet ground beneath it, and it was abandoned and left uncompleted until about 100 years later, well after Bonanno’s death.’
The tower’s construction began in 1173 and the hiatus lasted until the 14th century, with it being completed in the late 1300s.
‘I believe he thought it was a failure and no longer wanted his name on it. He passed from pride to shame and quietly dumped the stone on the building site,’ Ms Ammannati said, The Times reports.
Instead of becoming the Italian disgrace Bonanno feared it to be, the tower is now a central emblem of his nation’s identity and has survived for more than 800 years.
UNESCO made the Leaning Tower of Pisa a prestigious World Heritage site in 1987 and the United Nations organisation has since ensured it doesn’t topple over.
Builders in the 14th century made the floors at the top of the 187ft (57m) tower thicker on one side, to compensate for the slope.
But the weak ground continued to cause problems for the tower and its lean reached 5.5° by 1990.
Since then, work has succeeded in rectifying some of the tilt.
A complex, and cautious, plan was drawn up to stabilise the tower and make sure it did not crumble to the ground.
It involved depositing 600 tonnes of lead ingot beneath the tower on the soft side of its foundations to stop the depression.
At the same time, a series of tubes were drilled to help rectify the lean.
A year ago, engineers working on the project revealed it had been a success.
‘Thanks to this system, we recovered half a degree of lean’, said Robert Cela, technical director at the Opera Primaziale (OPA), the organisation who have been working to preserve it.
‘It’s still straightening… And many years will have to pass before it stops’, he said.
The Leaning Tower of Pisa has straightened by around 18 inches (45cm) since restoration work began in 1990.
It straightened by 41 centimetres (16 inches) until 2001, and another four centimetres since then.
THE BATTLE TO PRESERVE THE LEANING TOWER OF PISA
In 1987 the Tower of Pisa was declared a World Heritage Site by the United Nation’s cultural organisation Unesco, but as fears grew that it would topple over it was closed to the public in 1990 and engineers worked to stabilise it for the next 11 years.
‘The tower was on the verge of collapse, but we managed to stop the tilt and secure it,’ said Giuseppe Bentivoglio, from the Opera Primaziale organisation that preserves the tower.
The tower was reopened to the public in 2001 and remained open throughout a restoration costing almost £6million – partly to keep tourists happy, but partly because the revenue from ticket sales helped pay for the upkeep. The tower attracts over one million visitors a year.
In 2010 restorers made the tower even more stable by removing soil from beneath one side of its foundations. Its angle was previously 5.5 degrees from the perpendicular, but is now only 3.99 degrees off straight.
Experts say the seven-storey bell tower should now be safe from further intervention for at least the next 200 years.
But how did the tower achieve its lean? The most respected theory suggests the tower began to sink after construction – which began in 1173 – had progressed to the third floor after five years.
The cause was a flawed design – it had a foundation that was only three-metres deep set in weak, unstable subsoil.
Landmark: In 1987 the Tower of Pisa was declared a World Heritage Site by the United Nation’s cultural organisation Unesco, but as fears grew that it would topple over it was closed to the public in 1990
Back then that area of Italy was very belligerent, with various local land-grabbing factions jostling for position.
Because of the battles between Pisa and nearby Genoa, Lucca and Florence, the construction of the tower was put on hold for almost a century.
Thankfully this allowed enough time for the soil to settle – had there not been that length of break, many believe the tower would have toppled over centuries ago.
When tools were picked up once more, under architect Giovanni di Simone (who had built the Camposanto Monumentale, the fourth and last building to be erected in Cathedral Square) in 1272, the engineers built upper floors with one side taller than the other, in an effort to compensate for the tilt.
Because of this, the tower is actually curved. Construction was halted again in 1284, when the Pisans were defeated by the Genoans in the Battle of Meloria, and the seventh floor was not completed until 1319. Its stewardship at that point had passed to Tommaso di Andrea Pisano.
Just seven miles from the Mediterranean Sea on the west coast of Italy, the tower, which weighs some 14,500 metric tonnes, is frequently battered by storms that have eroded and discoloured it.
The distinctive, yellowish stone came from the quarries of San Giuliano, visible from the top of the tower on the green hills behind Pisa.