The tomb where Jesus is believed to have been buried in Jerusalem's Old City has been unveiled again after months of delicate restoration work.

The monument, which includes a 19th-century ornate edicule or shrine surrounding the tomb, is a key part of the Church of the Holy Sepulchre in Jerusalem's Old City.

The tomb was formally reopened on Wednesday in a ceremony attended by religious leaders and donors, following a nine-month-long and $3.7m renovation led by the church's three main Christian denominations.

The Greek Orthodox, Armenian and Roman Catholic denominations share custody of the church, but disputes between the three have led to renovations being delayed for decades.

Al Jazeera's Imran Khan, reporting from East Jerusalem, said the group of churches controlling the site had previously been forced to agree on a restoration plan as the structure was deemed to be unsafe by authorities.

"This is the first restoration that has taken place in about 200 years and is a considered as a historic event," he said.

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Centuries of candle smoke and visiting pilgrims had left the monument discoloured and almost black.

Parts of it were also coming loose, with warnings that it was structurally unsound and posed a risk to the millions who visit the site every year.

"Before this the monument was black," chief renovator Antonia Moropoulou told the AFP news agency at the site.

"This is the actual colour of the monument, the colour of hope," she added, referring to the restored warm reddish-yellow colouring of the momument.

Unlike other parts of the church, which were renovated between the 1960s and 1990s, the edicule had been neglected.

Moropoulou explained that they had systematically dismantled, cleaned and renovated almost all of the edicule, including the columns and upper and inner domes.

A window has been installed to allow pilgrims to see the bare stone of the ancient burial cave for the first time.

The new structural integrity means a protective cage installed 70 years ago by the British is no longer necessary.

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Samuel Aghoyan, the superior of the Armenian Church at the Sepulchre which co-financed the project, said that after the renovation the edicule looked "like a brand new building".

The work is not the end of plans to renovate the church.

Aghoyan said they have "tentative" plans to fix the basement of the edicule as well as the "entire floor of the church".

'All the layers of history'

In October, perhaps the most dramatic moment in the renovation occurred when the cave thought to be the tomb of Jesus was opened for the first time in centuries.

Marble slabs were removed to allow for the chamber's reinforcement.

They found a top slab dating from the era of the Crusades, indicating that the tomb had not been opened for 700 years, Moropoulou said.

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Underneath they found another from the era of Constantine the Great, the emperor who began the Roman empire's transition to Christianity in the fourth century AD.

"When we opened the slabs we discovered within the internal masonry all the layers of history - from Constantinian to Byzantine, to Crusaders to Renaissance," Moropoulou said.

Whether the site is indeed the place of Jesus's burial has long been a matter of dispute.

Some Christians believe he was buried in the Garden Tomb, outside the walls of Jerusalem's Old City, but Moropoulou said their findings supported the Sepulchre as the location.