As you come out from the Main Gate, you can see several of the major buildings of the Temple complex. To your left is the Oracle, housing the Temple's interactive divinatory oracle. Just beyond this, it the sculpture garden, featuring statues of famous personages related to the classical Greek Underworld. To the front, is the Temple of Hecate, and the sculpture of Hecate Trevia (the goddess in her classical threefold aspect). To the right, and out of view is the Temple Library.
This acropolis (or 'high city') was modeled in part after the famous Parthenon of Athens, and other sacred temple sites. You will note that the two buildings in view sit higher than the main plaza itself, with the Temple being on the highest platform. This was done to show that these structures housed things of greater spiritual importance, in ascending order.
Throughout the grounds are cypress trees. These were placed not only for their decorative effect, but also for their symbolic significance. Traditionally associated with graveyards and the Underworld, they are, like the willow, a symbol of the Goddess Hecate.