Fantasy - try the "Gormenghast" trilogy by Mervyn Peake - from the same era as "Lord of the Rings" and "The Chronicles of Narnia" but perhaps not quite as well known. Excellent (IMHO) TV version done by the BBC (who else?) around 10 years ago.
From the "Alternative History" part of the SF spectrum try "Pavane" by Keith Roberts, set in a "present day" Dorset (Corfe Castle features strongly) where Queen Elizabeth I was assassinated and the Spanish Armada/Catholics "won". For reasons not fully clear until hinted at the end society is...