Well it certainly does have the shape of a hippodrome. You using satellite imagery to locate potential or hidden archaeological resources is one of the main non-intrusive (no digging) methods used today, especially in England. So you are on the right track! The next step is to find out whether or not there has been any archaeological survey in the area or more specifically for that city. When I get a chance I will see if I can look up anything through the university or other professional sites. 

There does appear to be a theater and a religious avenue which ends in what be a sanctuary at the eastern end of the avenue. I do not notice any ongoing archaeology or what resembles recent excavations. I wonder if there has been any work performed there? Where ever there is a hippodrome, theater and sanctuary there is almost always a village! After all these things need to be cared for and it was always done by locals. 

That would be cool.

Here is a link from perseus.tufts.edu for Amphiaraios.

http://webcache.googleusercontent.com/search?q=cache:snStoYt51CQJ:www.perseus.tufts.edu/hopper/artifactBrowser%3Fobject%3DBuilding%26field%3DContext%26value%3DAmphiaraion+amphiaraion+archaeological+site&cd=10&hl=en&ct=clnk&gl=us

I'm using Google Earth for the satellite images, and the site nearby is the Amphiaraion of Oropos. I think that It was last excavated by the Archaeological Society of Athens in the late 19th century, though I know for a fact that later work has been done further south where there is a residential/commercial district, on the opposite side of the ravine which still has a creek running through it.

According to the wiki article, the locations of the stadium and hippodrome are still unknown.

I think what I found might be the stadium, as it appears too small to be the hippodrome, but who knows!

Thanks for the help & comments, guys!

[EDIT] Oops, we were posting simultaneously, apparently! I missed the above post.

Just took a measurement and you are correct about the size. The place you have found is approximately 140m long and 16m wide. A traditional Greek hippodrome is usually around 120m wide to accommodate around 10 chariots and is usually a total length of 210 meters in length. 

From what I can tell what you have highlighted is the stadium. I would assume from the terrain with the Stadium, theater and sanctuary all being located on the slopes of the valley that the only place for the hippodrome would be on top of the ridge to the north. Unfortunately it probably lays under all the agricultural fields in that area.

I believe I may have located something which would be approximately the correct length and width if seating was added to the circuit.

[Edit- do not want the information to get out!]

I may have to contact my aunt in Greece who is an archaeologist. First though we need to verify that the stadium and the hippodrome have never been located. This may be a cool discovery!

I'm having trouble with that link. :(

The way I did it was to take a screen shot (PrintScreen) which saves the image to the clipboard, and then I pasted the image in paintshop and saved it as a JPG. Then I hosted the image on photobucket and posted it here.

I'm going to go back and see if I can isolate the area you described though.

We make a good team!

Oh and tell your aunt that she stole my life, and I'd like it back! :p

Sorry about not posting an image, but didn't feel like dealing with all the extra steps right now. I also deleted where it is so that the information does not get out. I am going to do some more research on it and may make it my thesis, if possible, if you don't mind. You will of course get honorable mention for the stadium! I will have to get in touch with my aunt to see if it would be at all possible to go there and do some testing to see if what we found is actually what it appears to be. I will also have to check about permits and such. If it works out and I am able to get over there and do my thesis on it then when any excavations, if any, are performed I will make certain you get a personal invitation! 

If you want to discuss this further you can e-mail me at classarch1@yahoo.com. It's always best to keep these things somewhat private so that others do not take advantage of it and get on it first.

No worries. If I were in any position to actually investigate this myself, I would have done so and kept quiet about it until I could present the information as fact, rather than speculation. I posted this not only expecting someone to pick it up and run with it, but actually wanting someone to pick it up and run with it. I just wanted to have a part in it somehow. 'The beginning' is a nice part to have, and if you allow me to play that part then that's all I can really ask for.

However if you offer me the chance to be there in person, you know I'll be there.

I'd have bells on, but I'll have sold them along with everything else to get there.

Well from what I have researched so far, from JSTOR, ADS(English online scholar publications), Perseus Tufts, and even the Oropose Archaeological Survey performed in 2001, there is absolutely no mention of the stadium or the hippodrome ever being discovered. I have even read an account which supposes, wrongly, that the stadium is adjacent to the Stoa which runs directly in from of the theater. So it would appear that you are on to something! My mother is trying to get in touch with my aunt to discuss the possibilities of me going over there and doing some surface and soil investigations. This will have to be performed under the supervision of a Greek archaeologist who runs that area. I will have to write up a proposal and a methodology for this which will include all the historic research, previous fieldwork in the area, etc.

The good thing is that this can be my Thesis, as long as the topic is approved by my advisor!