It’s not on most tourist itineraries, but the British Library is a must-see for anyone who appreciates literature or history.
The permanent exhibitions are free and open seven days a week, and they showcase important documents like the Magna Carta (one of only four remaining original copies), Shakespeare’s First Folio, and early drafts of Beatles songs written by the Fab Four themselves. There are also original pages from Alice in Wonderland, a Gutenberg Bible, a manuscript of Beowulf, and countless other exciting items.
In my experience, there’s rarely a crowd at the library unless you happen to visit the same day as a school field trip. Should that happen, just come back later: the library stays open until 8PM Monday-Thursday, so you have plenty of opportunities to check it out!