As for Lambeau being the most famous football venue on Earth... well, that's really open to argument. Most people in the world have no idea where the hell the Packers play (save for saying "Packer Park" or "Packer Field" or, simply, "Green Bay"). And many who do, can't even pronounce it or remember the name properly. Down here, I've heard it called Lambert so many times it's not even funny. And we're pretty close to you guys so you'd think we'd get it right. For something to be the most famous on Earth requires remembering the name and saying it properly.
The most famous football venue on Earth, sorry starkiller, is the Rose Bowl. No questions asked. Pasadena, baby. After that, I'm not sure. None of them hold quite the esteem of some of the most famous baseball parks in the world like say, Ebbets, Wrigley, Yankee, Fenway, etc. Much more recognizable. And if you say "what's Ebbets?" I'm gonna smack you and take away your right to be a sports fan.
I would say that the most famous sports venue (regardless of sport) on Earth is likely to be Madison Square Garden. Again, arguable. But a helluva lot more likely than Lambeau as the most famous football venue. But, then again, since the Rose Bowl hosts a lot more events than just football, it could be argued as the most famous as well.