I love the Phoenix City Hall building. I am not sure what architectural style it falls into but it certainly is beautiful. The city hall building was finished in 1994 and designed by Langdon Wilson.
I took this photo of the Phoenix City Hall building from the roof of the 305 Garage. The parking garage is located kitty-corner to the southwest from the city hall building and is free. You can drive all the way to the top for some beautiful views. I have never been approached by security while photographing here, however if you are, always be respectful.