O.A.C.A. Olympic Indoor Hall

The Nikos Galis Olympic Indoor Hall of O.A.C.A. is a part of the Spyros Louis Olympic Athletic Center of Athens, was completed in 1994 and is the largest indoor venue in Greece. It was used for sporting events at the 2004 Summer Olympics. The venue is located in Marousi, in the northern section of Athens. During its construction, it was considered to be one of the biggest and most modern indoor sports arenas in all of Europe.

The 18,300-capacity arena also contains a training facility. Since 2016, it has been named after the Greek basketball player Nikos Galis.