What are the best ones in the world? Which ones are worth visiting just to see, and which have the best collections? Also, if you could have a proper library in your own home, what would it include? Also, post pictures of great libraries.

The nicest one in Chicago is the Harold Washington, but it's not really that great, not worth a visit just to look at. Though apparently the Chicago Public Library system has the largest collection of blues in the country or something. But that's the whole system, not any single library.

In my dream library: aside from the obvious, i.e., all the books I've ever liked or want to have on hand, I'd have shitloads of National Geographics, including the really old ones, which I have a thing for. And shelves tall enough to necessitate ladders (the rolling kind, of course).