Firefly Cellar is another location from the Candlekeep Mysteries 5E adventure that we've been steadily releases maps from for well over a year now. This partially restored library within the larger archives plays host to the Shemshime's Bedtime Rhyme adventure from the module and is characterized by using fireflies as its primary light source.
What's available for download:

Enjoy! Find more of the maps for Candlekeep Mysteries by clicking the "candlekeep" filter at the bottom of this post.