I was in Greece last week of October with my two nephews and I had promised to visit ancient Olympia with them. There are a couple of Athenian travel agents that organise private one day tours to Olympia. The one that I picked up was excellent. He has done great work about ancient Olympia. I don't want to be accused of advertising but if you search for "one day tour to Olympia" his websites will show right at the top. It took us 4 hours to get from Athens to Olympia and the whole tour was at our own pace. Comparing it to the 6 hours each way trip by train or 5 hours trip by bus, it is by far the easiest way to visit this great site and learn its history.
If you are planning to visit Olympia it is the easiest way to do it and I highly recommend it.

While on a Holland America cruise to the Mediterranean, we visited Olympia, the site of the original Olympics and the place where the Olympic flame is initially ignited before it starts its journey. We had an excellent guide who not only shared with us the history of the Olympics, but also had some unique postcards which, when rotated, showed the current ruins and then the original structure. As we discovered, the original Olympics was part of a religious celebration and the contestants were male only (yes, in the nude) who competed in track events that ran in a straight line forward and back unlike the current oval track. Outside the entrance to the stadium were pedestals which originally contained statues of Olympic cheaters along with the name of their therefore disgraced city. Wouldn't that be a great idea outside some of our current athletic stadiums?

My partner and I couldn't get enough of Olympia. To be able to stand where the runners stood, with your toes on the starting line and see the distance they had to sprint was truly memorable. The local museums are very good and explain the history clearly and succinctly. I was surprised that the place where the modern Olympic torch is lit every four years was so small and ordinary. A great place to visit, beautifully looked after too.

The site of ancient Olympia is very large and having an experienced guide is important. He or she is able to give you information about each ruin that if wandering alone, you would only see toppled stone and pillars.

You should easily give yourself a few hours to tour the ancient ruins and then another one or two to visit the museum a close walk away. Both are worth it.

Three facts I discovered from our incredibly knowledgeable guide, Cleo: each region held it's own "olympic games"; women were not permitted to participate or watch the games why? For one men trained and competed...naked; lastly winners had statue's created in their honour and so did cheaters....with the cheaters name, father's name and grandfather's name below...and they had to pay for it.

There are postcards by the outskirts of the park (and actually everywhere in Greece) that can give you a picture an aerial view of Olympia and a re-creation of what it may have looked like centuries ago.

There are something like 434 ancient sites in Greece not to mention just simple ruins and historical sites. I only saw a little but my opinion is that Olympia, Delphi and Meteora are must sees.