Since I guessed right with #14, I get to host the next one.
Q: What is When on Google Earth?
A: It’s a game for archaeologists.
Q: How do you play it?
A: Simple, you try to identify the site in the picture.
Q: Who wins?
A: The first person to correctly identify the site, including its major period of occupation, wins the game.
Q: What does the winner get?
A: The winner gets bragging rights and the chance to host the next When on Google Earth on his/her own blog! Tag it with “WhenonGE”.
Edited 20.3.09… since no one is even hazarding a guess.
And as a extra hint, the place is known in mythology for all its women killing the men (although this myth is not related to the site).