I have quite a few photos from Adelaide to post. It has a pretty amazing array of older buildings from the classically inspired galleries and libraries on the North Terrace to small bluestone houses. The most noticeable and celebrated buildings tend to be nineteenth century, however, I found a large number of twentieth century buildings that also caught my eye.
This is the Colonial Mutual Life building on King William St. It was apparently built in 1934 and became the city's tallest building until 1969. In a relatively low rise city like Adelaide it still towers above many buildings. I'm not sure exactly what you would call the style, I have seen it referred to as neo gothic, and certainly you can see the paired arched windows with delicate columns that are taken directly from gothic architecture. It has a relatively minimalistic use of decoration in comparison to most buildings that I would think of as neo gothic. Perhaps neo gothic filtered through the more streamlined aesthetic of art deco? The small columns look like twisted columns from a distance, but up close you can see that they are actually decorated with a very art deco zigzag pattern. The capitals are also very art deco, with the usual gothic style flowers or leaves reduced to simply geometric shapes and lines.
The building appeared to be empty, though apparently it does have heritage protection (and hopefully that counts for more in Adelaide than it sometimes does in Melbourne!) This site suggests there were plans for it to become a hotel, but it also says that it will be completed by 2009 and it clearly isn't.
Some close up details of the delicate decoration, which does get a little lost in the mass of of the very large facade.