May: Piranesi by Susanna Clarke

May's theme is: Haunting World Just Beyond Ours
Haunting, imaginative novels where mysterious worlds and unseen forces reshape how ordinary people understand reality.

The chosen book is Piranesi by Susanna Clarke.
A solitary man living in a vast, labyrinthine house of endless halls and tides gradually uncovers the truth about his identity and the mysterious world he inhabits.
245 pages, written in 2000

This has lots of good reviews so I'm looking forward to it!