AFTER being put on pause for more than a year, a major revamp of Scotland's National Gallery is back on.

Now priced at £22m, up for the previous estimate of just under £17m, the National Galleries of Scotland are to begin a major revamp of the key gallery in the centre of Edinburgh.

The troubled project was put on a "pause" last March when it was facing spiralling costs, many posed by the complex site: on a hill, in a major public park, under a listed building and close to a major railway line.

Now the galleries (NGS) have unveiled a new conception of the revamp, which will create new galleries for the display of Scottish art, and a complete rehang of the gallery space.

It will open in early 2021.

READ MORE: When Galleries pressed 'pause' on revamp project

The galleries have long wanted to change the display of Scottish art at the National Gallery, which for many years was shown in a "cramped and dark" concrete basement.

Work will begin in October, and the NGS say that the galleries will remain open throughout the redevelopment project.

However, to enable excavation works to the galleries directly beneath, the notable Playfair Steps, at the rear of the National Gallery, will be closed for the duration of the building work.

The Playfair Steps, designed by William Henry Playfair, are an historic steep flight of steps from the Mound to Market Street, and are often busy, especially during the Festival.

The new galleries, with large windows running the length of the new Princes Street Gardens facade, will have a "broader" look at Scottish art, and will open in 2021.

READ MORE: Stop and start history of landmark revamp project

They will feature the art of Allan Ramsay, Gavin Hamilton and Sir David Wilkie, as well as 20th century artists such as Charles Rennie Mackintosh, Stanley Cursiter and the Scottish Colourists S J Peploe and F C B Cadell.

The plan will involve "extensive new landscaping in the gardens", as well as a larger shop, and a new cafe.

The galleries say that once open, they will have a "dedicate family day" one daya a week, and more volunteers working in the galleries.

The first sign of the revamp will be construction work in October, followed by a new coffee shop at Christmas, and new steps and paths by next spring.

Funds for the revamp are from the National Lottery, worth £4.9m, and the Scottish Government, worth £5,5, as well as significant fund raising.

READ MORE: Director previously hoped for 2020 re-opening

Sir John Leighton, director-general of the National Galleries of Scotland, said: "This is a hugely exciting time for us, as we see our ambitious plans for the Scottish National Gallery getting underway.

"We will create the perfect showcase for the nation’s extraordinary collection of Scottish art, giving it room to breathe and showing it off with real pride to the world.

"This ambitious project will completely transform the experience of our visitors, creating a National Gallery that is even more open, engaging and inviting with new presentations of Scotland’s art in a setting that will be truly world-class."

Dr Tricia Allerston, co-director of the Scottish National Gallery Project, said that visitor numbers to the Scottish National Gallery have almost "doubled in the past ten years but fewer than one in six of them made their way to the cramped, dark spaces which used to house the national collection of Scottish art."

She added: "Soon, visitors will be able easily to discover, appreciate and enjoy our highly significant collections of Scottish art through a series of innovative displays designed expressly to engage them.

"Imagine looking at a painting of Sir Walter Scott and then looking out of the windows into Princes Street Gardens, a landscape created during his lifetime and which is now dominated by the great monument marking his international fame."

READ MORE: Sir John Leighton on national gallery revamp plans

The designs for the revamp are by Hoskins Architects.

The main entrance will be to Princes Street Gardens.

Aside from a short period in early 2019, the Mound precinct will remain open, and events such as the Christmas market will go ahead as scheduled.

Lucy Casot, head of the Heritage Lottery Fund in Scotland, said: “This is a hugely exciting time for Scotland’s arts and cultural heritage with the recent openings of Mackintosh at the Willow and the V&A Dundee and now the beginning of a wonderful new gallery, none of which would be possible without funds from the National Lottery playing public."