Piranesi by Susanna Clarke

Piranesi by Susanna Clarke, follows a man who lives alone in a mysterious, endless House filled with statues and an ocean. He records his life in journals and occasionally meets a figure called the "Other," who seeks hidden knowledge. As strange clues emerge, Piranesi begins to question his reality and identity. Spanning just over 240 pages, the novel blends mystery, fantasy, and philosophical themes in a dreamlike, haunting world.

Check out the goodreads review at the link below:
https://www.goodreads.com/book/show/50202953-piranesi