Dodona in Epiros, Greece. The oracle flourished from the 2nd millenium BC through to the 4th century BC. Zeus made his pronouncements in the whispering of the breeze in the leaves of a sacred oak tree. The oracle's messsages were interpreted by priests sleeping on the ground to be better attuned to the god's murmurs. The theater is one of the largest and best preserved in the legacy of ancient Greece.