Built in 338 BC by Phillip II of Macedonia to celebrate his victories in battle, the Philippeion has 18 ionic columns around the outside. It is not only unusual because it is the only round building on the site, but when Alexander the Great finished it, he added 5 statues of his family by Leochares to the curved base. This would have been profane in ancient times and made the function of this building different than everything else in the PanHellenic sanctuary.