The larger of the two outdoor pools, which seats 11,500 spectators, hosted swimming and water polo events.

But, due to the inflation of the Game's works and the constant delays, it was decided that the planned coverage would have to wait for later, which until 2024 has not happened.

According to preliminary assessments, the roof would serve to protect both athletes and spectators from the scorching sun and summer heat of Athens, which were even worse in the pools because of their location in the west.

However, this ended up not happening because of inflated costs and constant delays in other works that were more urgent and there is no option, FINA approved the holding of events in outdoor pools that received temporary bleachers to reach the minimum required capacity these bleachers were higher than the fixed ones and provided shade for the outdoor pools and other areas of the complex, but not for the present public.

The Aquatic Centre needed many service overlays, tents, and stations to host all of the behind-the-scenes portions of the 2004 Summer Olympics.