More like Excerpt from Neverwhere

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London BelowSeries
series5 books1996
Fantasy.
“Most notable is the appearance of the Floating Market at Harrods rather than under Battersea power station.”
from the catalogue
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The War of the FlowersNovel
Tad Williamsstandalone novel2002
Fantasy and portal fantasy, about fae, set in fairyland.
“More than 17 million copies of Williams' works have been sold.”
from the catalogue
Un Lun DunNovel
China Miévillestandalone novel2007
Fantasy and portal fantasy, set in otherworld.
“The title is derived from 'UnLondon,' the name of the alternate realm where the book is set.”
from the catalogue
Kraken: An AnatomyNovel
China Miévillestandalone novel2010
Fantasy, whimsical in tone, about gods.
The Paradise TrapNovel
Catherine Jinksstandalone novel2011
Fantasy and portal fantasy, tense in tone.
“Eleven-year-old Marcus is spending a week at the beach with his mother in a tiny old travel trailer, but boredom turns to terror when a new friend discovers a cellar that has magical doors through which people keep disappearing.”
from the catalogue
The Homeward BoundersNovel
Diana Wynne Jonesstandalone novel1981
Fantasy and portal fantasy, about demons, set in parallel universe.