The Rialto Towers (often The Rialto) is a skyscraper located at 525 Collins Street, in the western side of the central business district of Melbourne, Australia. It is the second-tallest reinforced concrete building and the tallest office building in the Southern Hemisphere, when measured to its roof (several other skyscrapers in Australia are taller if their spires are included, as are some other structures in Australia such as communications masts and observation towers). The Rialto Towers featured Melbourne's first skyscraper public observation deck which operated between 1994 and 31 December 2009. It was also the location of Melbourne's first Tower running event.
Designed by architects Gerard de Preu and Partners in association with Perrott Lyon Mathieson, the building was built between 1982 and 1986, opening in October 1986, and takes its name from the much older Rialto Building next door. The massive glass curtain wall façade of reinforced blue tinted mirrored glass is its central feature and changes colour during the day, ranging from a trademark dark blue to a brilliant gold during sunset. It is 251 m high, with 63 floors and 3 basement floors. It comprises two conjoined towers, the shorter North Tower being 185 m high with 43 floors. In total, there are 84,000 m² of office space.
This post is part of the Skywatch Friday meme.