True, and National Geographic is particularly skilled at hiding their URLs. In accordance with FR tradition, I did not follow the link until after posting, so I did not realize where you were. That site is a definite challenge.
You're right though, listing source was the way I got started on it. The first try was "inspect" (this was in the Chrome browser) and it gave me nothin'. Had to copy and paste to an editor and really pound some nails through it.