Three limestone columns of the temple of Nemean Zeus of about 330 BC have stood since their construction; and two more were reconstructed in 2002.[6] As of late 2007; four more are being re-erected.[7] Three orders of architecture were employed at this temple; which stands at the end of the Classic period and presages this and other developments of Hellenistic architecture; such as the slenderness (a height of 6.34 column diameters) of the Doric columns of the exterior.[8] The site around the temple has been excavated in annual campaigns since 1973: the great open-air altar; baths; and ancient accommodations for visitors have been unearthed. The temple stands on the site of an Archaic period temple; of which only a foundation wall is still visible.