Founded in 1807, the Boston Athenaeum is an old and distinguished private library, having hosted the likes of Ralph Waldo Emerson and Nathaniel Hawthorne. Its collection has half a million volumes, including an impressive selection of art, which is showcased in the on-site gallery. The library itself is open to members only, but tourists can visit the gallery. Tours of the library's art and architecture are offered several times a week; reservations recommended.