I still haven't figured out how to take good pictures at night, so my apologies for the fuzziness. This is the Mur Insel (Mur=the name of the river in Graz, Insel=Island in German). They built this along with the Kunsthaus and a lift in the middle of the city when Graz was named the "Cultural Capital of Europe 2003". There's a restaurant, a playground, and an amphitheatre on the Mur Insel.