Perth Arena

Location: Perth, Australia

Architect: Ashton Raggatt McDougall, Cameron Chisholm & Nicol

Based on an Eternity puzzle, this new area in Australia is one of the most stunning new sporting facilities in the world. It boasts a retractable roof (where!? and how!?) and seats a maximum of 15,000 spectators. The primary focus is basketball and tennis, though concerts will regularly rock the space too. Perhaps that's the primary reason for a retractable roof.