Temple of the Olympian Zeus, Athens. I discovered the advantage to being a student while in Greece. Of all the places I went I only had to pay once, and that was half price. It does pay to go to school! This particular ruin had very odd opening hours and we missed it a couple times, and on the day we did get in we were running to catch a bus, but it was still very cool. It must have been a huge temple when it was all standing.