The Philippeion.

It was a circular memorial with statues made of limestone and gold of Philip and his family, Alexander the Great, Olympias, Amyntas III and Eurydice I.

The Palaestra. It was part of the gym devoted to the training of wrestlers and other athletes.

The Temple of Hera.

There were columns like this laying around everywhere.

The Temple of Hera was originally made of wood. As the wooden pillars rotted they replaced them with stone. You can see the different styles of the capitals since the pillars were replaced over different periods. This is a Doric capital.