Traveling to ancient Greek ruins in Athens allows you to travel back in time. I am always amazed how the ancient Greeks were able to erect such immense and lasting structures without modern technology. The Temple of Zeus seen in this photo was completed in 2nd century AD and consists of Corinthian columns over 55 ft tall. In the gap between the closer structure and two distant columns, you can see the Acropolis in the distance with the Parthenon on top.