I have seen this tree in Spain and Portugal. Its leaves and bark bring to mind the American Sycamore or London Plane Tree, but not exactly. Also, it has three spherical fruits, an arrangement I am unfamiliar with. Like an idiot, I left my tree identification book at home and the Internet has failed to satisfy my curiosity in this matter. Any help would be appreciated.
As you noticed this is definitely tree from Platanus order.
Frankly, I think the one of what are you looking for is that Platanus orientalis. See it on a picture of seeds taken from Wikipedia.