I know I am not the only person who, on visiting a new city, checks out the library as a tourist attraction. An architecture blog has fueled the fire by proposing the 19 most beautiful libraries in the country.
http://www.curbed.com/2017/2/9/14551106/best-libraries-architecture-united-states.
Having recently seen the Geisel library at UC San Diego, it’s something else (although conventionally beautiful it is not). But no argument with the Boston Public Library, still my favorite library anywhere. 
The main reading room at BPL, a place I mostly go to write, rather than read.
Of the others on curbed list, in addition to Geisel (yes, of Dr. Seuss fame) and Boston, I have seen the Library of Congress (worked there for years in fact), the NYPL (pretty wonderful), The Peabody Library (although for an event, not to browse), The Washington Library in Chicago, The Beinecke (worth a special trip, particularly at sunset), the Law Library at UMich (which would not have made my personal list of bests), and the L.A. Library.
I would have included the Quincy (MA) Crane Public Library too, a H.H. Richardson masterpiece. And the renovated Cambridge (MA) Public Library is pretty fetching too.
A Few Reasonable Words 
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