Central Library in Edinburgh
Central Library in Edinburgh opened in 1890 and was funded with about $65,000 from Carnegie. He reportedly sent a telegram to the opening ceremony that said, "We trust that this Library is to grow in usefulness year after year, and prove one of the most potent agencies for the good of the people for all time to come." The French Renaissance-styled building sits on the George IV Bridge and loans out half a million books each year.
Interesting tidbit: In the late 1800s and early 1900s, libraries had separate reading rooms for women and men. Also, the first Carnegie libraries had so-called "closed stacks policies," where you weren't allowed to browse a library's shelves. If you wanted a book, you requested it from a staffer, who would get it for you from an area that was off-limits to the public.