The final pane of York Minster’s monumental Great East Window, the biggest expanse of staned glass in the country, took around 120 minutes to cement in place but marked the end of a restoration project that had taken 92,400 hours.
The jigsaw that is the East Window dates from the 15th century and would, if laid flat, cover an entire tennis court.
The return of its 311th piece, depicting the fifth day of creation and showing the hand of God blessing fishes and birds while an angel watches, was the last chance for many years to see John Thornton’s master glazing at close quarters. When the scaffolding goes, it will be visible only from ground level.
In 1405, Thornton had been paid £56 by the Chapter of York to create in glass the story of the beginning and the end of the Christian cosmos, from the creation in the Book of Genesis to the apocalypse and the second coming of Christ.
Its conservation, using modern weather-resistent materials, cost £11.5m and had begun in 2005, when the scaffolding went up at the Minster’s east end to allow stonemasons to assess the condition of the glass and stonework. Eventually, all 311 panels were removed, with the first tranche of 157 returned in 2015.
The completion of the patchwork with the return of what the conservationists had termed piece 15e, means the builders’ materials can be finally removed and the Lady Chapel beneath returned to use for worship.
The piecing together of the Thornton’s window had been, said the Dean of York, the Very Rev Vivienne Faull, a triumph.
“We look forward to seeing it in all its glory when the scaffolding is removed and the project formally completed in the spring,” she said.
The scale of the project meant splitting the work in two, with the second section of 154 Old Testament pieces returned one by one, from last November.
Each tile was around a metre square and took around 600 man hours to restore.
Sarah Brown, director of York Glaziers Trust, which oversaw the restoration, said: “This has been a once in a lifetime project for the team and it’s a huge privilege to be part of this milestone in the Minster’s history.”
She added: “The Great East Window is one of the great artistic achievements of the Middle Ages, a stunning expanse of stained glass of unparalleled size and beauty in Britain.
“The work undertaken as part of this project will ensure this masterpiece is preserved for hundreds of years to come.”
The project had been initiated after the discovery that following centuries of exposure to the elements, the Minster’s stonework had weathered so badly that the window had begun to bow.
The Heritage Lottery Fund contributed £9m to its repair, a figure matched by the York Minster Fund and the Chapter of York.
The conservationists will turn their attention now to applying protective glazing to all 128 of the cathedral’s medieval stained-glass windows.
Rev Faull said: “It will take us 20 years to achieve this but the environmental protection will stop the corrosion and decay caused by the glass being exposed to the elements, buying us much needed time for vital conservation work which will preserve the irreplaceable windows for generations to come.”