Young Adult / Adult Fantasy

Despite the less than stellar quality of literature, I found that I greatly enjoyed series such as Harry Potter and His Dark Materials because I could immerse myself in the story and be very entertained by them. For example, When I picked up HDM, I read all three books in less than 3 days, and then went on the wikis and the community forums and took in as much periphery information as I could.

Can anyone recommend fantasy books or series which will have this effect with the added bonus of being high-quality literature? What is the cream of the crop for the fantasy genre?

Try _Jonathan Strange and Mr. Norrel_ by Susanna Clark. It's a big book but is great writing. You won't feel embarassed carrying this book around or talking to people about it.

It's set in the Victorian era, centered around London.