The map shows the so-called World Wonders.
The red dots show where the 7 Ancient World Wonders were. The green dots show where the 7 New World Wonders are. If you click on each dot a pop-up with the name of the corresponding Wonder will appear. By clicking on the name you are re-direct to a Wikipedia page with a bit of history.
As a preview, you might want to know that only one of the 7 Ancient World Wonders is still in existence (can you guess which one?), so I think there are 8 World Wonders!