![The resident's pool at the Realm Adelaide.](/content/dam/images/g/u/1/l/s/4/image.related.afrArticleLead.620x350.gu17rz.png/1485762889491.jpg)
The two luxury penthouses in Adelaide's tallest apartment tower will cost $5.5 million apiece and give their new owners a high-rise address overlooking Rundle Mall.
Realm Adelaide, a 40-storey residential tower on Austin Street, was approved in December last year by the state government.
Each of the two double-storey penthouses will have four bedrooms, a private deck and rooftop spa. The penthouses will span 440 to 455 square metres.
The Elenberg Fraser-designed tower will rise through 40 storeys to 132 metres, potentially pipping Westpac House as the city's highest building. It is also facing competition for the title as the city's tallest tower from a 36-level mixed-use development on Frome Street. Developer Kyren Group submitted plans for that tower in July last year.
![Room with a view: an impression of an apartment in Adelaide's tallest residential tower.](/content/dam/images/g/u/1/l/r/y/image.imgtype.afrArticleInline.620x0.png/1485755394880.jpg)
Architect Callum Fraser was enthusiastic: "Realm Adelaide's golden geometric form will stand out on the Adelaide skyline, creating a strong architectural statement in the city."
Three-bedroom apartments will cost at least $1.185 million, with two-bedders at $455,000 and one-bedders at $345,000.
The new tower is being developed by private Sydney developer Parallel Property, which had already gained approval for a smaller, 29-storey tower in 2015.
The initial 94-metre version was given a green light even though the Development Assessment Commission noted that 41 per cent of its 272 apartments were below the minimum size.
But as the high-rise boom takes off in central Adelaide, the developer reworked its plan, revised its proposal upwards and resubmitted to the planning authorities.
![At home inside Realm Adelaide.](/content/dam/images/g/u/1/l/r/u/image.imgtype.afrArticleInline.620x0.png/1485755392699.jpg)
The tower has approval for 320 apartments, including 18 three-bedroom units.
As part of the development, the historic Assay House, built in 1858, will have its facade restored, with plans for a double-height bar and restaurant included.
The golden hues of the skyscraper are a tribute to Assay House's history, which in 1852, saw prospectors take their gold to the assay office where it was minted into the Adelaide pound, the first such coinage in the Australian colony.
Construction of the tower is expected to begin in mid 2017 and be complete by 2020.