Christ the Redeemer is 90 years old today... so how was it built?

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It is one of the most iconic vistas in the world and was unveiled nearly a century ago – on 12 October, 1931.

Brazil's statue of Christ the Redeemer sits on top of the 700-metre (2,300ft) Corcovado mountain overlooking the city of Rio de Janeiro.

Standing 30 metres (98ft) high, with arms stretching 28m (92ft) wide, the world-famous statue has become a cultural icon and was voted one of the New Seven Wonders of the World.

The idea for a Christian monument on Mount Corcovado was first floated by a priest in the mid-1850s to honour Princess Isabel, regent of Brazil and the daughter of Emperor Pedro II, but the proposal was dismissed after Brazil became a republic in 1889.

In 1920 a second proposal for a "Statue of the Christ" was made, motivated by so-called "godlessness" in society, and funded mainly by donations from Brazilian Catholics.

Designs included a representation of the Christian cross, a statue of Jesus with a globe in his hands, and a pedestal symbolising the world. The statue of Christ the Redeemer with open arms was chosen.

The statue was first made in France by French sculptor Paul Landowski, who created it in clay pieces.

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Those pieces were then shipped to Brazil to be re-made with reinforced concrete by Brazilian engineer Heitor da Silva Costa and French engineer Albert Caquot.

Christ the Redeemer also has an outer shell made up of 6 million soapstone tiles – some said to have notes written on the back by the workers who made them.

It took nine years in total to build the giant statue from 1922, when the first foundation stone was laid, to 1931 – and cost the equivalent of $250,000 (£183,000).

That would be more like around $3.6m (£2.6m) or more nowadays.

Materials were carried up the mountain using a railway, and workers reportedly used long wooden poles acting as scaffolding to construct the face of the statue.

The monument was officially opened on 12 October, 1931 – 90 years ago today.

The statue has been struck by lightning several times, damaging areas including the fingers, head and eyebrows.

In 2010 restoration work began, including cleaning the statue, replacing the mortar and soapstone on the exterior, restoring iron in the internal structure, and waterproofing it.

Christ the Redeemer was vandalised during this time, in what Mayor Eduardo Paes called "a crime against the nation".

The culprits, who had sprayed paint on the arm of the statue, later handed themselves in and apologised.

Watch: Brazil's Christ the Redeemer gets a facelift