The O.A.C.A. Olympic Indoor Hall (honorarily named Nikos Galis Olympic Indoor Hall since 2016), which is a part of the Olympic Athletic Center of Athens (O.A.C.A.) «Spyros Louis» (), was completed in 1995, and was the largest indoor venue in use for sporting events at the 2004 Summer Olympics in Athens, Greece. It is located in Marousi, Athens. It is considered to be one of the biggest and most modern indoor sports arenas in all of Europe. The 19,443-capacity arena also contains a training facility. Since 2016, it has been named after the well-known Greek former basketball player of Panathinaikos and Aris Thessaloniki Nikos Galis. Construction Nikos Galis Olympic Indoor Hall is notable for its distinctive A-frame roof that features four huge pillars, each of which is 35 meters tall, that stand 108 meters apart from each other. According to the Greek Ministry of Sports, it is the largest indoor sporting arena of its kind in the world. The arena is also constructed in a unique way so that an abundant amount of natural light comes into the arena during the day. The arena seats up to 17,600 for gymnastics events, although only 12,500 seats were made publicly available for the gymnastics competition at the 2004 Olympics. It seats up to 18,989 for basketball games, which includes 18,500 regular seats for the fans, 300 seats for the media members, and 189 seats for VIPs. A large scale arena renovation was completed in 2004, for the 2004 Summer Olympics. The arena was then renovated again in 2016. 2004 Summer Olympics The arena was used for artistic gymnastics and trampolining, and also hosted the finals of the basketball matches at the 2004 Summer Olympics. Renovation of the building for the Olympics was completed on 30 June 2004, and it was officially reopened on 10 August 2004, shortly before the beginning of the games. Basketball use The Indoor Hall is the regular home court for the Greek Basket League professional basketball club Panathinaikos. It is also the primary home court of the senior Greek National Basketball Team. The arena was used to host the quarterfinals, semifinals, and finals stages of the 1998 FIBA World Championship. In addition, it was used as home court of Maroussi B.C. in some European games. On 4 and 6 May 2007, the Indoor Hall hosted the EuroLeague 2006–07 season's Final Four, the semifinals and finals rounds of Europe's